Ollie, I'm not so sure I'm with you on this one. Full size airliners use basic barn door types to good effect for minor corrections with the ailerons only coming into play for the more meaningful requirements.

But I do agree that some experimentation is in order to determine the size and placement on the wing. I'm thinking that there is a reason why the roll control spoilers on the airliners I've flown on and the MU2 are placed far to the rear on the airfoil.