My rotational save it is around premade households, but I'm playing only TS4 base game. I really missed Sims 3 characters diversity at first glance on TS4 when it was released, but now I think its cast is incredible as TS3 cast used to be. To accomplish it, I needed to go through SimGurus profiles to get those promotional Sims and Maxis profile to get the rest of them (and some special as Star Wars ones... it is amazing to look Yoda playing with my Sims kids at the park or Vader drinking at the bar hahaha). Also SimCreator050 has some good Sims from trailers (as Dyana Fire and Drew Current from ghosts trailer).
Right now, I'm still on first generation (but rotated two times all 10 households . I let them loose to choose what they want to learn, or to whom they want to talk and everything that Autonomy let rolls (like when try for a baby). I usually rotate between households whenever someone grows up (and I let all unplayed Sims without aging to always fill the city with people - if I want to add one of them at the rotational, I just move'em to a home and start to play). My only usual interference on Sims lives are to help them accomplish their whims (sometimes I only buy new items to their homes when they wish it). The best part of this rotational has been doing social events - it reminds me a lot of my memories from TS1 House Party events that used to be so cool (cake, cake!).
I've also noticed that my Sims seems to be more interesting now that they grown skills and relationships. The game flows better and there's some quite random funny things (Nina Caliente using a voodoo doll at the bar, people visiting my Sims homes and using different objects). I don't know, could be only my impression but I'm really touched by it hahaha
I love rotational play ❤️