I think there were far too many neutral critters that moved around far too fast. It was almost impossible at some points not to declare war on an entire species by accident.
I like having 'normal animals'in the game, and the fact you can attack them if you want to isn't a bad idea, but I think it needs to be harder to attack a neutral creature - like shift-right-click or something - so that it's an act of deliberation not something you end up doing by accident.
