Todd..... Maybe another motor with less cells would work well, and keep the total weight down, this would have the second advantage of not requiring as much money to get performance. my limited experience has been that most people grossly overpower their electric models...either to " impress the glo guys" ( which it doesn't)
or just because they can, and hang the cost. I don't know who does your calculations, but what if you calculated your stall speed, then use a pitch speed of 2 1/4 to 2 1/2 times the stall speed?
You likely will find that you can get much more thrust than the model weighs, adequate speed, and cut the cost and weight factor way down on your power system. Aerobatics is not really speed related,within reason, so who cares if your model is not super fast ( 90 mph??) most don't fly that fast anyway, maybe if the max speed was about 55 or 60 mph. but the thrust was over 12 pounds ???