since d3 tennis is all about the experience (there is no $$ right?).... so yeah, the grades are priority #1....
the tennis - yeah, the FH is good.
BH - the 2hbh drive, you spin like a top and fall backwards... there should be weight shift / stepping thru the ball, so you finish on the front foot (the right foot).
the slice - too vulnerable.. no bite, no pace... emulate Federer... really throw your racket edge at the ball as if you want to cut the ball in half, this will ensure you have absolute face control, and allows you to lean into the shot and push forward to get penetration.
Volley - needs rebuild.