I really like Swordsman they have a good hit rate and deal good damage, but if your planing tournaments I'll suggest you a Fighter (in case you prefer human characters/ actually i think that the best PvP character are Nameks Shadow Knights) because Swordsman use too much RP, so that will make harder (no impossible) to win in tournaments.
you want a healer, the best healer in the game are Dende, but i think that Pokos and Ultimate majins can do a good work too (sorry but I dont know too much about wonder majins

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