sorry, you did show some serves... lol... the groundstrokes part is so long i lost patience
the serve... you are pushing the racket thru the ball, instead of whipping the racket head..
try a couple of analogies -
1) if you think throwing, you should be throwing the racket HEAD, not the entire racket.
2) if you think hammering, you can imagine hammering a nail right into a piece of 2x4 at the contact point..
hopefully these thoughts can change your body language of the serve.