Class/Social Rank
Sims of course have no sense of social status, the poor do not kowtow to the wealthy, the employee does not kiss up to the employer. While I don't try to impose a class structure on my Sims, I do want to have a sense that the Founder family are like the local 'lords' of the village. Once Chess Founder became a successful, rich businessman, I instituted a rule where if he came to visit another family I was playing, he had to be greeted, even if it was not a convenient time.
This rule has been extended to some of his children, and will continue to extend to his descendants as long as they remain the most important family in the village. Which of his descendants enjoy this rule is a subjective decision on my part. As with all 'great' families, some members are less than others, and have less social status, and people don't kowtow to them all equally. Chess' daughter Meadow is also successful in business & is very conscious of her social status, so people treat her as they do her father. No one feels any need to kowtow to Risk Founder at all. Between those extremes, Harmony Founder as the heir to the farm, must be greeted if she rings your bell, or if you happen to be outside while she is passing. Hyacinth must be greeted if there is a child in the house enrolled in her school, or a former pupil. As I type this Sage Founder is in Uni, and has not achieved any kind of social rank, so no rule for her yet.

Other business owners also have a bit more status than non-owners. They have to be greeted when visiting the homes of their employees.

Townies
This neighborhood has only 4 CAS created Sims, Chess Merchant (Founder), Mystery Founder, and (former) YAs Ash Brown (Founder) and Kelly Green. I also moved Maxis made Sim Tara Kat, and her 3 cats into the neighborhood (Pets EP). One of my goals is to not create any other new Sims for this neighborhood, to rely entirely on the townie pool for mates to breed the coming generations. I'm also moving townies into the neighborhood, marrying them to each other & breeding them.
I use the Sim Logical teleporter to move townies into a playable Sim's house, and then the newly moved in townie uses the newspaper to move out. This method stops the family who is temporarily hosting the newly moved in townie from getting any extra money from the deal.
In cases where a townie is being married in or moved in as a permanent new resident, I will use the in game 'move in' (or 'get married') interaction.
If I run out of townies, I will generate more, if they don't generate themselves. (I have removed the notownieregen mod, so they may regenerate. So far none have, so I don't know how low my townie pool numbers have to sink before they will regenerate new ones.)

Seasons and Time syncing
When Seasons first came out, I made a big deal about keeping all my families in season with each other, and I was generally tied the idea of keeping everyone in sync.
In this neighborhood, I'm not syncing Seasons at all. Newly moved in Sims start at the default starting season, or if they purchase a previously owned home, they start where the last resident left off. It does make my story a bit surreal, with a Sim being in summer on her own lot showing up at friend's house in winter in the next scene.

I do try to keep my families in some kind of sync, so that related children are aging together at the same pace. But it is not a strict syncing, sometimes a Sim born earlier than another will actually transition to childhood a little later just because I played his family a little less. As long as I don't have one Sim born around the same time as another entering college while the first is still being potty trained, I'm okay with a little discontinuity.

As far childless families are concerned, I'm even less worried about syncing. I have some moved in townies that I moved in because I wanted them to have scenes in their homes. I don't find them interesting enough to play them in regular rotation. So they will age slower than some of the playables they've appeared with in the story. They may not age at all if I have no reason to play them, like they were still townies. I'm okay with that, I tend to think of them as townies with houses rather than as 'playables'.

The base hood & all subhoods are set to the default Seasons seasonal calendar, except Uni, which has alternating Spring/Fall seasons only. (see Education section for more about Uni)

Skilling and Education

Skilling:
One of the goals of this neighborhood was to take skilling out of the home and into the community. I use Pescado's community lot skilling hack so Sims can earn skills on community lots, and built lots for Sims to skill in. I've always hated the fact that Sims can max out all their skills so easily, so early in life. So I'm restricting their skilling so they don't max out even one skill before going to college. Some are lucky enough to find one to focus on to earn enough points for a scholarship.
I started off by banning bookcases, computers, easels, chess tables, pretty much anything for skilling. Sims could buy books from owned businesses to study from (or read for pleasure). A sim could have an easel, or other skill object, if they'd already reached level 6 of the skill. Another based on character kind of thing: if a Sim has already spent enough time painting on community lots, they can finally make it a part of their home life. A novelist of course needs a computer.
Since Free Time, I've had to change this. Literature hobby Sims can have bookcases, and I've also been allowing more Knowledge Sims have them, as they would actually be likely to have lots of books & need shelves. I've also been allowing more computers, since they now have so many more options for hobbies. I'm happy to report that not all of my Sims can actually afford even the cheap computer (I use Pescado's anti-humble hack, so they don't get free hand out computers) so the computers haven't yet become ubiquitous.
Free Time came with new skill objects, and added hobby enthusiasm to the old ones, so I've relaxed my stance on skilling objects. Sims can have skill objects that reflect their new hobbies, and may obsess over them.
Generally, when a Sim is home skilling, I make them stop after a skill point has been gained & make them do something else, so they don't power skill.

Toddler education:
Toddlers are allowed skill toys. In fact, I like to give them a range of choices in skill toys, as many as their family can afford & has space for. Toddlers are trained in all toddler skills (learning to walk & talk, potty training, and now with FT, nursery rhyme, though the last is not required.) usually by a parent or grandparent, sometimes by a 'nanny'. Not an NPC nanny as they are banned. Some families with two working parents & no elders on the lot will move in a live-in nanny (from the townie pool) to care for their children.
Except for the training sessions, toddlers are free range. I rarely direct them to do anything: I do check on them & direct them to the potty, bottle or sleep mat if hunger, bladder or energy are getting too red, but I let them choose how to amuse themselves. They have skill toys & non-skill toys to choose from & those lucky enough to live in homes without foundations can wander outside & chase fireflies at 3am. Looking foward to the day when one cuddles a visiting wolf. I use the Sim Logical endless bottle & no empty potty, and Atavera's toddler sleep mats to give my toddlers more independence.
If a toddler is using a skill toy, I usually stop them once they've earned a skill point & make them go somewhere else. They may then choose to go obsessively skill on that object some more, or find something else to do. The point is, I don't just let them park themselves & skill without interruption.

School:
Primary Education:
Crescent Island starts out with no public education system at all. The first generation of Founder children were entirely homeschooled, using Inge's Flexi School option.
Once Hyacinth Founder became an adult, she opened the first school in the community (Sim Logical School system). All children are now enrolled in Hyacinth's school. She teaches them to study (I love that every child has the 'Learned to Study from Hyacinth' memory, and that she has a memory for teaching each of her students) using the gradework. Her school also provides ample opportunities for skill building & hobby discovery.
Children enrolled in the school don't go to school from their home lots, (the school system brings them in while you are playing the school lot, but when you play the families of the students, the children will go to the public school unless you use the School Changer to change that). Most of the kids get put into the 'Flexi School' and stay home. I had one case where the child's parents both worked 9 - 5 as managers of owned shops, so I ended up enrolling the daughter in the Prep School (Sim Logical), which has 9 - 5 hours, so her parents could both go to work & she wouldn't get taken by the social worker.
Hyacinth's school is technically not a 'public school', it is not funded by tax revenues. Parents must pay to have their children educated. Hyacinth doesn't charge a flat fee, it depends on how much the parents can afford. The Kats for instance, own a business & have around 50k of accumulated wealth, so they pay 2,500 simoleons per child. The Spitzigs, both employed as shop managers, paid 1,000 simoleons for their daughter's education. The Turners almost got away with paying nothing because their shop doesn't make a lot of money, but they took a big cash bonus for gaining a business rank, and so were able to pay 2,500 per child (they have twins).
I use Pescado's money order to send the tuition money to Hyacinth.
It is possible that some future parents will choose to completely homeschool, but so far all have sent their kids to Hyacinth's school.

Secondary Education:
Hyacinth's school is for children only, once her students turn teen, they are 'graduated' and don't go to school at all, leaving them free to work in their families' businesses where applicable, or to get jobs working for other neighborhood businesses. Teen 'career' jobs are also banned.

College:
Despite having no secondary education, everyone goes to college, Crescent Island University. I considered no uni at all, but there aspects of it I like, so I decided to do it & try to make the aspects I don't like better. I don't like how easy it is for everyone to get a GPA of 4.0. Because I've reduced their ability to earn skills during childhood, I do send kids to college who actually have to earn skill points to pass, rather than just doing meaningless class work for the grade meter. I've built academic buildings for them to earn skills in, trying to make the campus more real & useful.
Free Time actually has done a bit to make Uni more interesting for me, Sims can go to the Arts building to earn badge points in sewing & pottery, as well as paint for Creativity, or to the Science academy to earn mechanical & logic skills, and use Science & Tinkering hobby objects. Still, I find 8 full semesters is too long, so I use Pescado's college clock to send kids to exams as soon as their grade meters are full, rather than living through every minute of each semester. I'd like to have more Sims getting less than 4.0, but even if they go to exam with a less than full (but not in the red) grade meter, they get a 4.0, not a 3.3 or 2.7 that I think they should get. I don't want to get into manually changing grades etc, and I feel really weird about deliberately stopping them from going to class & not having them do assignments. I want them to try & still have a chance of failure. Failing deliberately isn't really the solution I'm after, but just showing up earns you summa cum laude in this college. I've decided to just live with that. It's not like their degrees have any meaning once they graduate.

I also considered not sending the kids of non-shop owners to college, as a way to impose a sense of class/status. But, this would have first impacted Astrid Spitzig, a Knowledge teen with parents that work as shop managers. I liked her too much to deprive her of the education she wants, I like her enough to want to play her as a YA. My wants trump everything in my world. Though uni is free of course (maxis style) I did make her 'earn money for college', by raking leaves for her neighbors & by getting a job in Chess Founder's grocery store (where her father is manager). The time she spent working, and doing chores and maintaining her garden at home, prevented her from earning the 8th Logic pointed she would have needed for a scholarship, so she went to college with less money than others.
In the future, I may have Sims that don't go to college. I've had one drop out. This will always be based on character rather than on how rich or poor the family is. Real world college is expensive, Maxis college pays you to show up. I've decided in this case not try to impose real worldism: here, there is no monetary barrier to higher education.

University has alternating Spring/Fall seasons only, imitating the fall/spring semesters. Of course the seasons don't quite correspond to the semesters, especially as semester length is variable based on when I send them to finals. Having two autumns does help defeat my desire for Uni to be harder, but Sims also cannot fail in Spring, so the extra autumn just helps me get through some semesters faster.

Transportation
I have banned cars as transportation, and use 'walk to lot' to get everywhere (BV, FT). Well, I shouldn't say 'banned', cars exist in this world,
I use taxis for dates since they don't allow you to walk across the street when you are on a date, and Sims that are employed in owned business take the carpool to work, and on the rare vacation, Sims take the shuttle. It is possible I will someday have a Sim with a thing for cars, who will buy one, or several. The no car thing is more of a preference on my part, I like the walk to lot much better than driving, and it satisfies my inner green to see a town where people don't need cars.
I have decorative bus stops all over town: they are a unifying element, and I pretend that Sims 'walking' to different subhoods are actually using public transportation rather than walking the whole distance.
FT introduced the restorable car, something I've wanted since Sims 1. I will allow Sims to use this, but only rarely. I don't want to see every street lined with broken down cars. In fact, zoning laws prohibit this, only Sims living on the outskirts of town will be able to have restorable cars. out in their yards. In the more populated areas, you'd have to keep it in a garage. Currently no houses have garages.


Allowed/Banned objects, Aspiration & career rewards

Aspiration rewards: I've never been a big user of aspiration rewards. There are many I've never used ever, and some I've used only to see them in action once. The only ones that ever were part of my regular gameplay were the elixir & kibble of life, smart milk and the weather/season changer. In this neighborhood, I'm banning smart milk. The elixir & kibble of life are allowed.The weather thing is allowed, but I haven't used it. (see Seasons & Time)
I use TJ's Age Duration mod, which makes the adult span longer & elder shorter, for Sims that transition naturally. CAS adults have the default 30 day span.
I'm not specifically banning the other rewards: if I have a criminal minded Sim, she might want to use the counterfeit machine. I might use the energizer for a Sim inclined to be building odd looking contraptions in the basement. Basically, I won't use them if there is not a story driven reason to use them. So, if you don't see a Sim in pictures using an asp reward (except for life elixir), assume they aren't being used.

Career rewards: Since I've banned careers, most of my Sims won't be earning them. Townies are given random careers by the game, some of them at high enough rank to have earned rewards. Any townie that moves in must quit his/her career, but may keep any earned career rewards.
I also use DJS Sims' 'Bob the Reward Gnome' aspiration reward to get certain career rewards. Very few Sims will get career rewards this way: mostly it will be for business owners to enhance their owned businesses. For instance, Chess Founder has two execuputters in his game club.
Some Sims will get career rewards for personal use, based on their characters. Jade Ng, an art student with the LTW to be top of art career, got the art career camera when she graduated uni. She can't have the career, but she can have a camera.


Game Cheats/refresh objects: I have never once used the max motives cheat, or any other cheat to raise needs or aspiration bars, and intend to continue not using those cheats in this neighborhood. I do use snapdragons, sparingly. I only have 2 playable Sims that can make them as I type this, both moved in townies that came with gold badges. Neither of them owns a flower shop. Scott Kat, one gold badge florist, has given a few of his snapdragons to Chess Founder, who uses them in his shops to keep his cashiers perky. The Kats uses them in their shop for the same purpose. At some point, some one will open a flower shop & there will be more snapdragon availability. But I never have relied on them, so they'll probably remain something I stick next to cashiers.
Note: I had been briefly using aromatherapy pots by Parsimonious, they work similar to snapdragons. Trina Turner, into the paranormal & New Age thinking, had a shop based around those aromatherapy pots & also the buyable potions from parsimonious. It turns out, the aromatherapy pots interfere with the toymaking bench, so I had to get rid of them. (Trina has now turned her attention to UFO research, she still has her shop & sells potions, but lets the manager run it while she hangs out at Area 53, hoping for a Close Encounter of the Weird Kind)