Well, whatever it becomes, I want in when it comes to truly brainstorm.
Maybe a berry collecting job. And about the hunting, it's cool, but it might be too big. To simplify, you could use any Melee or gun. The whole island/land could have the effect put upon players where they receive body parts or whatever. Any weapons should be used anywhere.
Another idea I was thinking of would be a dinosaur egg hunting job. Every time you pick up an egg it's either 1.) An egg shaped rock, 2.) An egg, or 3.) a npc dinosaur appears to attack.
Weapon ideas(since I can't upload right now anyway)
Boomerang, rock launcher(rocket launcher, except no rocket. Just a big rock.), a bone rifle that shoots out wooden spikes, etc.