I see you agree with Systemic Anomoly's analysis in post 15.
Have you watched the videos I posted in post 9?
It sounds like you are quite athletic, and have learned a serve technique which up until now has served you well.
But you will never reach your potential with your current serve.
And I'll bet with your athleticism that you can learn it quicker than most - just that it is painful to seem to have to suffer through more double faults for now to make that progress.
Your coaches are trying to teach you to throw the entire left side of your body up and at the ball.
This slow motion video of Soderling shows specifically the leg drive and cartwheel action you need.
Robin Söderling serve slowmotion http://www.youtube.com/watch?v=a56pvP1i6x8
If you learn to do this it will be a powerful leg drive and cartwheel of the upper body to power your serve.
You then can't help but land on your left leg.
Please keep an open mind to your coaches and let them help you make the necessary changes in your body motion, ending up with your landing on your left leg.
Your landing on your right leg is just a symptom that your current serve is not correct.
Again, I would urge you to watch those two videos and see that the new serve motion will lead to a better serve.