I am an intermediate/beginner player & my serve is really gud, best part of my play, in matches i can win many points with my serve but i was talking to 1 of the coaches in 1 of my clubs & he told me about looking at where the reciever is which i kinda do, its obvious that if they r quite far back from the T, to serve short & if they they r very close to the T, 2 try the occassional flick serve. Wat i found i did not do thou was look at the position of their racket, whethers is on the left or right side, their grip etc. Once i did this, i found more weaknesses in players so therefore better chance of getting a better start, more of a chance to attack first. You do not want to hit onto the forehand side of the racket, you want to make it awkward for them such as having 2 change grip etc. I ave seen in the lower levels, players stand in bad positions wit bad racket direction but these get a lot less the higher the level. It also made me tink about my position & if i was giving away a chance due to bad positioning or bad racket direction. Im a relative amateur compared to many players on this forum so if u ave any more advice or tips or comments in this subject, please tell .