Don't get frustrated. Just take it one step at a time. First, if your plane is doing really bad stuff, you probably have a sloppy and flexible linkage. Check the integrity of your control system first. Second, I believe that your C.G. is too far forward. I fly my 40 size Extra at 4-3/4 back. You should need just a small amount of down to hold inverted. Warning, aft C.G. will increase your control sensitivity. Third, you probably need some right thrust. Holding hard right rudder on take-off is a good indicator. Start by adding 2°. Fourth, I still get a slight corkscrew in my loops. I have started to learn to compensate with rudder or aileron as required. I think if you want F3A precision, you have to fly an F3A airplane. However, you can get pretty close with a properly set-up sport scale aerobatic plane.
