His per-36 in preseason is 26 points, 15 rebounds and 3 blocks.
Honest questions, what's a reasonable expectation for his GP this season?
Well either he stays healthy or he doesn't, I guess. We've seen success with bone grafts for guys like Kevin Durant and Brook Lopez. I think people assume he will injure something else. Maybe so. I'm not sure why he'd be any less fragile than any other player, though. If his foot isn't a problem than his risk of injury is probably about the same as Jaylen Brown.
One note about his Per-36... his usage must be super high during those 12 mins he's been playing. His minutes have been limited so they are basically getting him very involved in the minutes he plays. That's the partial explanation for why he has better stats than Jaylen Brown in 10 less minutes. It's also the partial reason for why his assists are low... he's basically trying to score in every limited possession he gets. I've heard commentators say he'll play more team-style once he has consistent minutes in the flow of actual games, but for the time being, the coaches just want him to get some reps trying to score. He seems to be improving every game, though. He supposed to creep up to 18 minutes tonight so it'll be interesting to see what he does with the additional time. Expected to get 20-25 minutes once the season starts. They still claim he'll be held out of back-to-backs. It's still not the regular season, though. Let's see if he can stay healthy through the preseason.