In addition to what others have posted above you're falling backward off the majority of your forehands - even short ones you should be on-top of. See these two pics - which are typical of most in the video.
On your backhand slice
you step or veer away from all of them. Again - most of these you should be positioned better and, ideally, leaning into.
Additionally - re: the way you hit - all those shots of your partners which go out >> hit them
. If they're in the air >> hit them.
You're wasting all those opportunities to practice launching the racquet head/hitting on the rise etc.