The problem with evaluating KO as a player is that when he's playing well, he looks like a quality starter, and sometimes even better. He's had (short) stretches of games in both seasons where he's been clearly the best player on the floor and repeatedly made plays on both offense and defense.
But then, of course, when he's playing poorly he looks like a deer in the headlights and like a guy with no business even being in the league, let alone on the floor. He still does make some contributions in those cases but usually of the subtler kind, like creating floor space and moving the ball along. But man, on the obvious stuff he looks terrible.
Of course, he's not as good as the good games, and not as bad as the bad ones, but he really doesn't seem to wind up in the middle very often. It almost reminds me a bit of Rondo's early seasons, when he'd look like a world-beater for 2 weeks then have a terrible slump for the next two. KO's probably never going to peak as high as Rondo but he has that same maddening tendency. Hope he smooths it out as he matures.