I agree with the others, check and correct the CG balance before anything else. By the way, what engine and prop are you using? What is the engine speed at idle? That doesn't fix the CG issue, I know. But after you correct the CG, the engine idle speed and prop pitch will become factors to consider as well. I have never heard of flaps needed on a trainer. Furthermore, if you are going to set up the flaperon function on your radio, you will be sacrificing aileron authority. That will come back and bite you if you are landing slow with the flaperons down and not have enough aileron control.