I enjoy seeing you playing, knowing that you have problem with your knees.
How do you guys plays drills? do you play several drills first, then he does the same? Looked like he blocked the whole 17 minutes and you did different exercises. I would have trouble cope and also focus for so long time. Maybe you guys would benefit more if you play one drill a shorter time then change. Maybe it is better with longer drills if you are working on something. Do not know what works best.
I think your forehan looks pretty good, but i think your backhand also seemed pretty good in a match i saw. But here i think you are pretty passive with the backhand. I think you could try to close the angle of the racket, accelerate more so you brush the ball more and be more aggressive with it in general. So your backhand will become as good as your forehand! If you play to soft in a drill it do not think it will be natural to get a block back because an opponent will attack the ball instead.