You have very good preparation here. Your chin is overlooking your right shoulder,
your weight is being transferred to your front leg, whch is properly positioned across
and in front. Your left hand is on the throat of the racket which assures a good
shoulder turn. However, you need to raise everything upward to take advantage
of gravity as source of momentum into the ball.
To match the pro takeback, straighten your arm out just a bit more and lift your hitting arm.
Lift your hitting arm by getting your hand to shoulder height. By extending your takeback up and back, you will generate
more momentum into the ball.