Your opponents can steal your sheep. This saves lots of time for your village to stockpile berries. The boar is tough to kill. You need at least 5 villagers to successfully hunt a boar without losing a villager. If you have the time, try to lead a boar back to your town center and then hunt it there.
Deer are very easy to hunt down.
It only takes one villager. But deer can leap pretty quickly when being hunted and this may lengthen the distance between the deer and your town center. Build your farms close to your town center and mill. Wolves will attack you and chase you down until they've hurt you. Two villagers can kill a wolf, although one might not make it.