It's been said already, but I think it's worth mentioning again. On your backhands, you are pushing back off that front foot rather than driving forward into the ball on it. It does have a good bit to do with your front foot's placement, but I think that it also has to do with a bit of a late or rushed swing. Otherwise, the form looks pretty fluid and grooved.
Minor things to change on that side would also be your takeback. It could initiate more of a shoulder turn. At the end of that stroke, I think you are opening up your shoulders a bit too soon. I do think, however, that is more of a function of you not driving into the ball. If you can direct more of you power to the ball, rather than around and up, I think your shoulders will stay closed for a longer period. The stroke is a bit rushed, overall, I think. Forehand, too.
But, you are seeing the ball well, and striking it with authority and confidence. And your feet are very active, and your footwork pretty sound, though as Bungalo Bill said, you could do with a bit less jumping around. Man, don't you get tired?!