Decreasing wing incidence is the wrong thing to do. Downthrust is what is used to keep the pitch from increasing with throttle increase. Downthrust works because it hits the bottom of the stab/elevator. The more throttle, the more it affects the pitch. If you decrease the wing incidence you will have to add up trim, so the prop wash will not raise the tail.

Draw yourself a picture of just the wing and the prop and you will see that downthrust and wing incidence are exactly the same thing. All that changes is the position of the fuse. The stab/elevator has to follow the wing incidence, either by changing the stab angle or by elevator trim.

Sorry, it's harder to explain in words than it is to see it--hope you can make some sense of this.

With a scale model I think it's best to have a computer radio and couple some elevator trim to the throttle. Both thrust line and wing incidence are pretty noticable so it's better if you can leave them alone. Jim