in my opinion, forests are nothing special but trees, i think deer would be a great addition, droping venison that you can cook and eat. you wcould also capture and breed them. at first they would be provoked, but eventualy, you would be able to tame them. what do you think?
Hmmm... I'm a little against taming, it would actually be nice too have passive food mob that you didn't tame.
And maybe they would run away when you get close, like an ocelot, graze grass like sheep, and maybe you they will auto breed and form herds.