More variations probably, and more interactions with smaller objects. I think they have said that they are looking into new ways for different sims to interact with each other. I would not mind different animations when they are sitting and talking, so three sims that are sitting down in a sofa will all sit differently and they will move their hands differently when they are talking.
I also think for standard animations that you use a lot and when it's supposed to be romantic or serious the animations should be more subtle. We can still have over the top animations for rare occasions like failing to cook something but not for animations that we see often in my opinion.
Their idle animations should also be more subtle, I have never liked that sims are smiling with a large smile and laughing when they are happy, which they often tend to be.
Sims should also heat up their leftovers in their microwave, for suitable leftovers, not salads...
