if you were to really work at that, i think its great!
But i think you should make it so if your a boy you get to be pikachu, and if your a girl, you get to be...
So its like there are two options.
Also, with the no humans thing, i like it, but that would make the map all trees and stuff, like you said,
I would still make humans, just you can't talk to them, like they're in the backround.