Actually, I think they should just make regional versions of the game itself. Asia/Americas/Europe, and divide the cars accordingly.
HEAR ME OUT.
Any sports-car-or-better (i.e. 200hp+) would be universal, included in all versions. But, the "daily drivers", the little 80hp putter cars, would be region-specific. So the Asian version of the game would get the Daihatsu Midget, but the others wouldn't. I mean, the car wasn't even sold here, what's the point? So instead of putting in these worthless, obscure Japanese cars that we've never heard of, our version would, instead, have a bunch of American daily drivers. Ford Tempo, Saturn Vue, etc. And the European version would get cars like the Fiat Panda and the Smart Four-Two. Cars that are actually sold in the area that the game is released, cars that we actually know and see on a daily basis. Me, I've only ever owned "normal" daily-driver cars.. I've been through four of them, and not a ONE has ever appeared in a GT game.
And, as I said, sports cars and up would be in all versions.. everyone would see the Skylines, JGTC racers, etc... everyone would see the Paganis and the Corvettes (and the Ferraris.. here's hoping).
What do you think?