Ok I read the Ultimate answer thread and saw there will be character customization, but I think a different idea, or something to be implemented on top of that original idea, would be choosing characters from the game. For instance:

Bug Catcher
Lass
Hiker
Super Nerd
Gamer
Team Rocket Grunt
Beauty
etc...

And based on who you pick, it changes your choice for starter pokemon. For Instance:

Choosing a Team Rocket Grunt
your 3 options for a starter are: Rattata, Zubat, & Ekans

Choosing Beauty
your 3 options for a starter: Oddish, Bellsprout, Nidoran (female)

Choosing Bird Keeper
3 starter options: Pidgey, Spearow, Farfetch'd

Swimmer
Starters: Tentacool, Horsea, Shellder

Hiker:
Starters: Geodude, Onix, Machop

and so on.

Who wants a bunch of Ash's running around the map? Not me.