What a blast!
A am running a Grayson Hobby GH2212-10 with a 9x6 prop and a 20 amp speed control. Plenty of power and no problems with torque roll with a straight mount.
I did not build this plane with a swappable fuselage. My plane also wanted to nose up even when going slower. Even with a 2200mah 3cell pushed to the nose. I had to trim it up a lot. I shortened the push rods on my Ailerons to give the wings a bit of downward push. Maybe this will help?
I also did not have a great landing strip so I kept flopping on my nose which weakens the wing and supports.
SUGGESTION:
Double up the wing support and add some barbeque sticks. It is solid now! The motor can handle any extra weight for sure. See picture below. Also added clear packing tape on leading edge of wings and on the bottom front nose. When you go nose over you will beat up the nose.
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