I only watched a few shots. On your BH vs backspin you take the ball way way earlier than on FH. On FH vs backspin, you are backing off and waiting till the ball is falling, long after the top of the bounce. If you do that, you have to arc the ball so it lands on the table. You can't make it a really fast shot without much arc because your contact point is after the ball has dropped below the net.
But, long before you address that issue, you have to reset after each shot way way way faster. You are not ready for the next shot coming at you and so you are reacting to the incoming balls after they are on your side of the table. You have to be ready for the shot coming to you before your shot bounces on your opponent's side so you can watch what your opponent does with the ball BEFORE he has actually hit the ball. If you only see where the ball is going after it bounces on your side, there is no way you can be anything but late.
The reason you are slow to react to the incoming ball is that you need to reset much faster and be ready to watch what your opponent does with the ball as he is doing it. You stroke is fine. But you will continue to be late and taking shots from out of position as long as you are still watching your shots and not resetting much faster.
