RE: effect of down incidence
You can't just look at the wing alone. You need to compare the angles of the wing, stab and thrustline to see the whole picture. This stuff doesn't care what angle it is to the fuselage but it DOES care what the angles are between each of those three things.
So to help us give you a proper answer other than the ribbing you've mostly see so far you need to give us more information.