Let me start with this - I'm not a college coach who reviews highlight tapes for high school kids. Therefore, take what I say with a grain of salt and see if anyone who does review them chimes in with opinons that mirror mine or not. I mention this because every single time I see a high school highlight video, I think they're too long. It's supposed to be a highlight reel, not a playing of any play that showed a semblance of positivity. I would look at the HUDL reels for any of the top kids that were blue chippers last year and copy their format. If they're all using 30+ plays, so be it. If they're not though, you can use them as a barometer and trim the video down to about 3 mintues.
Second thing, it appears as though your son might be tipping his pulls. I'd have to give the film a couple more watches to know for sure, but on a couple plays, he is sitting further back in his stance when he's pulling. I knew before the snap he was pulling and that was on the first watch. Also, if he's planning on doing a linemen camp this summer, find one that will teach him how to use his hands. I find hand placement and usage to be one of the most overlooked phases of line play at the high school level. You'll see top dawg recruits, especially on the defensive side, get tagged with statements like "violent use of hands." On offense you can't be as violent by nature, but you can be violent and accurate with placement. If he can get better with his hands, he will likely see his offer list improve.
Other than that, I wish you and your kid the absolute best. Enjoy the ride!