The only case where I wouldn't want animals showing up one after another (or very often, etc) would be with the sharks and other marine life. The amount of sharks in Far Cry 3 annoyed me.
But yeah, as stated by Killerfist, it's different fighting bears with pistols and hunting knives, than it is using a flamethrower or SMG's. Or blowing it up with a car.
As for what I don't want... I'll repeat again: Glitchy cover system and bulky animations. Not that I expect them though. Red Dead (and Max Payne) cleared those ones up, and the cars are supposedly heavier like with racing games (which they're quite familiar with) so I don't expect disappointment to be an option.
Get rid of modders and I'll be ecstatic.