some suggestions:

a "retirement" hut. once your villagers become elderly, they have to stop working and retire or else they die sooner. and if not a retirement hut, then they just stop working once they become elderly and start playing with the kids.

teachers. only a master at their trade can teach and you can pick and choose which kids learn what trade (ie if their detail screen says they have some research skill, you can click on that and they can get "taught" by a master scientist) they should at least be able to learn enough to be at the trainee level when they finally turn 14. maybe once you get a master at something, you have the choice to turn them into a teacher.

aprenticeship. once they turn 12 they follow around a master of a certain trade and they don't actually do any work, but they learn more about their trade. this could go with the teaching, instead of having all of the kids go to school, only those like 12 and up (or 10 and up) can go to school and have a master become a teacher.

I like the ideas of skinny dipping and other real behaviors like napping. they also should sleep and the night and day would be fun, one of the puzzles could be creating fire to allow them to work a bit later (but they still sleep). the cook and the tailor would be fun as well. you can't have a cook until you can create fire and you have to make a loom to make clothes.

seasons. this could also go with the tailor, they have to make different types of clothing for the different seasons. this would also make it more exciting to play, like there's a blizzard and they have to stop building and the kids can go ice skating for fun.

weather, like above with the blizzard, but if it rains, you have to stop construction, but it makes your crops grow faster. this could also incorporate other puzzles too, like a research hut or tent (so you can see inside)

and being able to sort them by their age/sex/trade would be really nice.