well, in canada we have a ASW/ marine patrol aircraft called the aurora, I think it is very similar to a p-3 orion, but better. Anyway, the ailerons on it aren't directly controlled, I think the elevator and maybe rudder is same. On initial t/o roll, they all flap, completely uncontrolled. As airspeed picks up, they "castor"(for lack of a better term) into position. These control surfaces are controlled solely by trim tabs. If this was done on a model, it would solve the servo/backlash problems. Also, if a full flying surface was properly balanced, i think this servo tab system would work