The best powertrain for this vehicle is Saito 180, swinging 17x6. It's light to keep the CG right, and will waterfall this plane silly, and may even do an ascending flat spin when the flap-elevator is coupled.

Aft CG does not make up for poor 3D skill, but great 3D skill does not make up for unacceptable CG either. Both the plane setup and the pilot skill complement each other.

I peeled the bottom fuse covering aft of the wing. Once you see the wood structure (or the lack thereof), you won't be surprised that any impact will break this fuselage stick structure. I am gonna repair the sidewall stick structure, but add a balsa sheet at the bottom all the way to the tail. This should improve its lateral rigidity. Ever notice your tail is flimsy left & right?