Yeah... most videos I see of him, KRU gets stunned or fractured quickly, then dies before he can really do anything. And his big damage attack, even if it hits a stunned target, isn't anything to really be scared of. One of his abilities should come with some sort of self or team cleanse, and the stun should be non-removable for a couple of turns.
But maybe people just haven't found the right way to mod him yet to really give him the proper damage or survivability. Dunno.