I did not see this suggested already, so here goes
I'd love to see a sort of "character creator" added to the game where we could literally just fuss around with genetics and try out different combinations and such. It would be nice to see what a certain genetic combination looks like before breeding for it in game, especially once you hit the point of breeding for appearance.
Bonus: Creatures from the character creator can be named and saved/loaded/edited at any time, and maybe even imported from the active family trees of your current tribes.
Bonus bonus: Saved creatures have a chance of appearing as wild creatures in-game that can be added to your tribe! Maybe this could be expanded to having some sort of "online library" where you could upload/download characters? Or, of course, people could do it the good ol' fashioned way and just share the files manually.