It has to be said???? If your instructor did not instill this extremely basic aspect of flying from day one its time to either do refresher training or get another instructor.
With all due respect, this is making a mountain out of a molehill. I and everyone else I have ever seen using a Cessna type push throttle who places their hand where the knob is at the back of the hand with the index finger extended forward along the throttle has a very comfortable position with extremely easy and precise control. Friction is set for individual comfort. "bracing your hand on the panel" - sorry that's ridiculous.