From Nauroto to One piece. From Samurai X to Pokemon and from Fist of the North star to Berserk the characters and worlds in anime have lots and lots of original powersets and world rules. But they often also have somewhat an plausible feel, danger seems more real and threatening situations are explored more in detail, often quite extensive detail, giving anime and manga a different feel that western comics even though they have insane amounts of variety.
I think that the only roleplaying game that can capture all these powers and stunts is the Hero system. Anything else will be bogged down by an increasing number of rules as in anime almost all combat ready characters have an special ability or two needing their own set of rules.
I think Hero have a huge opportunity here where they can make source books for anime. Anime art commissions are also cheap as hell compared to everything else so it would be possible to put some cool anime art on the cover and in the book to draw in the kids. Make some kind of generic anime setting like One Piece or Nauruto. Filled with different factions and power sets who all come from one or two sources. Anotother option is "dark vampire hunting world" or just plain mecha.
Thats just what I think though. I dont know if it would be a success but it sure seems popular.