Sorry, Just sometimes it's difficult to understand just how basic one needs to be when explaining the basic theories. With a symmetrical airfoil, and even more so with a rather blunt leading edge, CG can be instrumental to offset the normal very small amount of up elevator trim which provides the down force used to load the wing needed to provide the positive AOA to produce adequate lift to fly the machine, and this can be very noticeable at slower speeds.
Pattern fliers try to balance rather tail heavy, near 40% MAC, and get away with it with their very lightly wing-loaded, long tail moment, highly powered designs, using very minimal control movements. The aft CG then assists their trim changes about the lateral axis when transitioning between inverted and normal maneuvering.
Your experiences during the slow flight regime proves my point as the AOA increased, you became somewhat behind the power curve and the aircraft could not fly out of the extra drag due to the higher AOA which also produced the lift required for the level flight or slight descent. The aft CG replaced up elevator which produced the situation only because of a given speed in a given condition. Drag is also a function of the square of the airspeed as well as lift.
No big problem, many have the same misconceptions about those factors and all seem to work OK. H-ll they're just toy airplanes .