Looks solid .....not sure where others are seeing very little lower body action. I see a little bit of leading with his lower body versus initiating the swing with the hands, although he does a good job getting his lower/upper body into correct position at impact. Pause it at 34 secs to see a textbook impact position.
Hands drifting down is obvious on some swings. He could practice some loading in front of a mirror. Would like to see a little more evenness and synchronicity between hands walking away as front foot moves toward toe down as he appears to move the hands back quite a bit immediately before the front foot moves much. That may help to not initiate the swing with his body moving so far forward immediately, which will be an issue if he recognizes off-speed stuff too late.