If it makes you feel any better...
NONE of these nations would be bullies... because they would be unable to defend themselves. They would rely on some bigger, stronger ally to guarantee that other nations would not trample their sovereignty or, most importantly, their property rights.
I DO think that a bigger, stronger nation would dominate in the area that would be formerly known as California... I just don't think that stronger nation would be one of the new nations formed.
It would probably be the US actually.
So the rich of the new nations would not dominate the poor of the new nations...
It's far more likely that the US would dominate both.