Neat flying plane.
I damaged the first wing and flew it with tape wrapped over the holes in the leading edge. Can see the tape over holes in the leading edge of the left wing, at the launch of this video. https://youtu.be/ybawO-EKDr4 . Later reprinted the wing using 2, 220mm center sections for lighter wing loading. Landing has to be attempted pretty fast. I have had some wing slap in flight.
Heat is definitely a problem at the motor mount. Since the motor is enclosed and does not receive much air. Perhaps Michael would redesign a very slightly fatter (maybe 10mm) front fuselage starting at the motor area with some vent holes.
I used the slicer program to stretch out the vertical stabilizer. Felt like particularly with a bigger wing more drag at the back would be appropriate.
LIked your use of sand paper to help stabilize the wing mount.