He's not bad, relative to some of the back-up C's. He's no Ajinca. He's most likely overpaid at his current salary though.. He would greatly benefit playing with a PG like Schroder, that can really collapse the defense at will.
There's an element of flimsiness to his game.. I've been checking in on Hezonja for years, so I've seen him play more than a few times. He's mobile, but don't get that twisted, he's like 2nd round pick quality, IMO. Walter Tavares is a much better 7'3" prospect..
Tomic is markedly better.
IMO Lyles is better, the offense relies on players making good reads late in the shot-clock and Trey's obviously much better than Pleiss with that. Lyles had a nice dump off to Hayward to start the game, which was promptly blocked at the rim, was still a nice pass though.