FWIW, Rocco Zikarsky would likely be an upgrade over Walker Kessler because Rocco can score in different ways outside of 5 feet, and he can take a dribble or two. His skill level seems to be comparable to his countryman Andrew Bogut entering the league, though he doesn't have Bogut's wide body.
Rocco is like 5 years away from maybe being a better player than Kessler.