... They make a Pokemon version where you have access to all the regions?
from Kanto to Unova. Just some random thinking. I'm thinking this would be great and
will have lots of play time. I know there are many positive and negative things to this but I'm just thinking.

This is a topic that has been touched on many times before, and the overall response has been "Nope, never going to happen." there are numerous reasons for this, from Nintendo losing money, to various game play aspects.

Not to burst your bubble or nothing, it's just not going to happen in the foreseeable future. The way I look at it, we may get one of these "go anywhere, do anything games" if (and this is a really big if) Nintendo and Game Freak is going to die as a franchise and want to end it with a bang.