Jim Messer is right.

I have the Hanger Nine Cub flying with an Astro-Flight Geared 40 electric motor. I have the elevator at zero degrees incidence and it flies better than a friend of mines that has the stock positive incidence. Like Jim all of my designs have the engine set at zero degrees, stab set at zero degrees and the wing at 2 or maybe 3 degrees incidence. Even if the scale 3-view shows positive incidence in the stab I always put the stab at Zero incidence.

So if you Hanger Nine Cub flies tail high add 1/4" balsa underneath the trailing edge of the stab and you will notice the plane flies level...

Good luck