@Monkey:
Using a Japanese cast in NYC would be completely weird and make no sense.
You could make an Italian cast, a Jewish cast, a Chinese cast, a Dominican cast, an African cast, Irish, Jamaica, Puerto Rican….
But for all it's diversity, New York has no meaningful size or presence of Japanese people (unless you want the adventures of a biker gang of photo snapping middle class Japanese tourists going to that Radio City Christmas crap). It would be extremely bizarre and kind of dumb to make them Japanese.
And for most of these groups anyway, in New York it would be hard to come by a realistic stance where you wouldn't have a multi-ethnic cast. Except maybe the black and hispanic groups. In which case American Akira just becomes a sci-fi version of Juice or something.
I should've specified better, I meant use a Japanese cast in japan, or change the names.
I just realized that New York is on the list of cities destroyed in Akira though….
http://www.mangareader.net/101-2004-8/akira/chapter-1.html