1) They have specified that they aren't adding albino cats or, for that matter, hairless cats due to certain health conditions for those cats that make it hard to live.
2) There are certain accessories that look phenomenal, I once got a cat with a neon collar and it was black and rainbow, and it looked pretty cool. His name was Rigatoni as well, favorite cat I've gotten. So yes, there are "bling cats" in the game already, just gotta get lucky.
3) I believe the devs are actually working on something for the fresh kill pile. I think they have talked about it a bit and there even was a prototype in a dev version once apparently so it might be a WIP atm.
4) Idk what they are doing for genetics, but I'm pretty sure it is not on the devs to-do list since it isn't really as big as a feature as other things :P