Pokemon Should Look and Play Like This

[Zac]

you can already play through each region (by playing their game of origin)
why do so many fans think it's so vital for all of them to be crammed into one game?

also there's no good way to manage parties in that scenario, as sticking with one party for that long would make the diversity of the regions pointless (and probably cause some leveling problems) while forcing the player to start a new party would undermine the spirit of the game