Certain things get altered for this game, for a variety of reasons, so when characters are input into this game, the developers try to take many things into consideration, including the players opinion on the usefulness or desirability of the character. Plus, the game already had Sasuke Susano'o, who is immune to Pure Ninjutsu damage.

I don't know man, I think having the character * with the anime depiction would be better. Just makes the most sense. I believe that would be more desirable.

If we followed too closely to the anime, everyone would have the exact same 2 or 3 characters, because they are so overpowered there is nothing that could counter them, besides themselves, with the nerfing and changing of characters, it creates more of a variety of teams.