TS4 things you miss in TS3 (this is no "which-is-better-discussion"!)

I don't switch between the two. I tried TS4 several times but still prefer TS3. I did enjoy using CAS, I think both the vampires and the toddlers are well done and I like some of the building tools such as adding foundations. I also think some of the paintings which came with the base game were excellent, particularly the jazz posters.