Man these are some really cool ideas.
I'd like to add though that just for free roam there should be an addittion of a 'World' settings in the settings menu that opens up after you beat the game. Options like turning off hostile wildlife and hunters could be there.
Sometime I just wanna terrorise some beachgoers without bloody hunters in my way.
Again some really cool ideas and would definitley love to get bigger and fae pre-historic monsters but also the current maps would have to be resized as you lterally wouldn't fit in them any more haha