I wd say animals, they cd be better in all the ways! And there shouldnt be a option in the poll called 'Time to load large zoos' Its not the game's fault, after all they are large and b4 when I had less ram it used to take hours(kidding) but know with my knew increased ram it loads in no time (in 5/6/7/8 secs) You can't blame the game(ryming) its your ram! (This is like saying "I don't have water reflection(ingame)" without having a goog graphics card!)
Whereas for the other options you can't do anything about it!(Having a high Graphics Card doesn't change the looks of the animal or make them realistic)!