I'm a big Perk fan, but I wasn't impressed with his basketball moves in the video. He should be working on finishing off his shots higher, gathering and making his moves quicker, and finishing off plays off the move. He should be getting three layups/dunks off passes/rebound putbacks for every post move he practiced.
Perk's conditioning and body looks good. Despite him going into his 9th NBA season, the guy's still just 26 years old. I'm looking forward to seeing OKC's progress this season (hopefully)