RE: NEGATIVE ELEVATOR STAB INCIDENCE - NEEDED?
Set the engine to look scale in angle - - a litle downthrust won't harm any thing on that design
zero zero setups are best for very light models which are aerobatic
for a nice scale cruiser , a lil bit of decalage will be fine
of all the adjustments you can make to trim - downthrust is the least effective.
The relative angle between wing and horizontal stab is the most effective.