RE: Incidence Questions
I would think you want more than "zero lift" at speed, as you need enough lift to keep the airplane flying (unless you''re airplanes have no mass to be lifted into the air?). I would also think the "ideal" angle of attack would depend on the given segment of flight (IE..in the straights, turns, ect).
Flying on a race course is a huge compromise. Most, if not all, racing airfoils never reach their "best" angles of attack in either the straights or turns.