Maybe for the child sims, adding a mini pre-teen stage? but not too obvious, where it seems like they have to incorporate new bodies, but instead.. maybe as child sims get close to their birthday, maybe a slight height growth? voice changes, still keeping things the same.. but with slightly updated changes, if it's possible to program it that way. & Yeah, more added activities centered around those growth milestone changes, rollerblading, biking, maybe a Sims version of Tik Tok, (even though that's a bit beyond my generation & not my thing) but still, more Simstagram related stuff, pranks. Stuff like that.