I think his basement is MCW if he can't develop an NBA shot - he does a lot of things pretty well. His ceiling... well... if he can stop guys sagging off him and going under screens to take away his passing lanes by knocking down the 3, his ceiling is pretty darn high.
I still think he's more of a trick passer than a Jason Kidd as far as being a floor general goes... Seems to prefer the tricky pass than the right basketball play (ie. shot) when going to the basket, which is almost Rondo-esque at times.
I would've drafted Fox over him on draft night, but Fox is much more of a boom/bust type of player IMO. Fox's shot motion is definitely easier to fix, at least... and he's closer to the other elite PGs that have come into the league over the past half-decade or so in size/athleticism. Ball is pretty unique, which might be a good thing. We'll see.