As mentioned before, on a wing mast, reduce the rotation to assist with depowering.

As for optimum, fully powered up settings....

Maintaning attached flow around the leeward side of the sail is the most critical and hardest to achieve. You want a smooth flow from the leeward side of the mast to the leeward side of the sail. Attaching some tell tails a few inches back from the mast will assist you in seeing what is happening with the attached flow behind the mast. (see pic)