I don't want more lifestates between what's already there or gradual ageing, I find that it would be entirely pointless.
I don't want to "free the baby," I think they're fine as is, like irl you can't do much with babies, other than feed, clean and play with/stimulate their minds which is all you really need in-game.
Preteens are a bad idea and are certainly not needed, if anything, something needs to be done to differentiate between Teens and Young Adults in the game as they are far too similar imho.
I don't have a burning need for body-hair to be added to the sims, (other than beards).
I think mermaids are fine as is and I don't miss the underwater lots, diving or houseboats from TS3.
Edit: I am indifferent towards a farming pack and university. I went through enough hell of my own with Uni, I don't want to send my sims through that.