What is your favorite feature, even tiny one, in the franchise? (Not just the "main" games!)

I actually liked TS3 Stylist option that you could go to other people's houses and make them over as an assignment. That was my ultimate use of all the CAS items <3

In the beginning of TS3 I was so bummed that I could'nt play more families at the same time like in TS2, but now I like playing with one family at a time( just not too long..always having too much ideas)