Trying to get a true time from a video like you presented is tough. But if he is a true and consistent 1.88 that is fantastic. Obviously accuracy is important.
Blocking the biggest thing that jumps out to me is his left leg. When blocking both legs need to be behind you, the glove blocking the "5" hole and the throwing hand behind the glove. He keeps his left leg out creating a very large 5 hole and almost picking the ball as opposed to taking it in the chest. Meaning it looks like his glove hand comes up with the ball when it bounces instead of just letting it him square in the chest protector. Sounds like it sucks (it does) but that is the proper way to block. In the first block attempt it appeared centered. He still dropped to one knee and when he did his body came forward. This will make keeping the ball close to you harder when you block it as well. Framing there wasn't a lot of examples... Make sure he has proper glove position when he receives...I would suggest keeping glove a tad lower (around batters knee). Makes pulling up lower pitches easier and less obvious, plus its a great place for a pitch.
What kind of formal training has he had at the position if you don't mind if I ask?