My views on Thompson + Zeller ...
I think Tristan Thompson is already an above average defender and rebounder for the power forward position with excellent defensive potential. However, he has shown little to no skill-level offensively yet. He has no jump shot. He has no shot-creation skills. He is not a passer. He is strictly a finisher around the basket.
On a decent team, Thompson wouldn't get more than 15-20 minutes a night due to his offensive limitations. The only reason he is playing so much and putting up such numbers is because the Cavs suck.
Until he shows more offensive talent, I think Thompson is very much a question as far as star-talent goes ... but I do think he will be at least a solid rotation player for a long time. He is already a serviceable backup PF due to his solid defense and rebounding. By adding a passable jump-shot and fulfilling that high end defensive potential, Thompson can become a Taj Gibson like player (high end role player, glue guy). So I believe Thompson has good pedigree as a long term contributor but still has a lot of uncertainty as far as star talent.
I think Tyler Zeller is a deficient defender and rebounder at the center position. Too much of a lightweight in each department to ever be a quality starter. His potential maxes out as high end backup center but I think he is more likely to end up a middle of the pack to slightly above average backup center than a high end one. Good jump-shot and mobility.
I don't know what to make of Waiters yet. Too early.