Hey TurfGuy, You have a nice little pitcher there. Only one thing I would start to incorporate into practice and bullpens is forward momentum. He has the first part of pitching down and that is the very beginning of leg lift. He lifts his leg and with a very subtle move loads his hips. Improvement can start when he brings his leg down. He is a typical young pitcher that brings their leg up and then brings their leg down without generating any forward momentum.
You can really see this when he takes the ball out of his glove, no forward momentum. I would start teaching him how to use his lower half more efficiently. Other than that, he sits well into his delivery and rides down the slope of the mound really well. He is in a good position just before foot strike. Arm is coming up and he is still closed. In maximum arm external rotation he has opened up really well. Good glove position and a solid landing leg. Really nice follow through as he stiffens up his front leg. His leg rotates nicely over his back hip.