I trim all my planes these days for hands off flying at about 1/2 throttle. The trainer because half throttle or just above is where the plane is flown. My pattern and IMAC planes have a neutral CG and they will fly until they run out of fuel straight and level at half throttle with hands off. I don't really use the radio trims much, a beep here and there as the weather requires. My control surfaces are set at zero degrees up and down. CG is your friend. A flat bottom wing is designed to lift with speed so it's another animal.