Add elemental affinities for the various players, with what affinities you have being affected (of course) by family... for example, Haku would be Water/Wind affinity period (since they use ice jutsu, a combination of water and wind), Uchiha having an affinity in Fire, and an open one, and im not too sure about the rest of the clans :O but effects of affinity could be the jutsu's get a modifier bonus if the affinity and jutsu type align... for example, a lightning uchiha's affinity would boost the power of its Chidori... maybe have the second affinity unlockable at Jounin, and randomly chosen then... and primary chosen at random on char creation, or whenever they take the 'paper' test that kakashi used.