RE: 3rd plane ideas with ailerons
I built a Stevens Aero Stik for my first aileron trainer. Moved my Slow Stick brushless motor/ESC/Receiver to the Stik and it is a great trainer capable of outside/inside loops, rolls, inverted flight, slow flight, fast flight, etc.
Building and covering it was fun and quite a learning experience in and of itself. Learning to set it up for flight was also an excellent learning experience.