Not a tv-series, but I thought AKIRA was pretty kick-ass. It does sort of fail one of your criteria...
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... but I think that's the point. A member of a biker gang gets super powers, and the results are about what you'd expect if you gave god-like abilities to an angry, jealous kid who's scared and confused.K1CKER said:- no super exaggerated overpowered characters, all the special powers they have are reasonable.
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Crap, beat me to it.Owyn_Merrilin said:OT: Try Akira. As in the movie from the 80's. There's a reason it was such a strong gateway anime back in the day, and it's well done enough that it can still stand as one today. I'll also second Full Metal Alchemist as having a lot in common with Avatar, but as a pure example of the kind of quality that is possible if you dig for the good stuff, Akira is incredibly tough to beat.