"in your opinion do you think the Moki 1.80 or 2.10 will liven it up for possible mild 3d action? "

Don't know Kid, because installing a big Moki will entail adding 2 or 3 ozs to the tail which will add at least a pound overall to what is already a 12lbs plus aircraft. At 13.5 lbs either Moki will take it unlimited vertical, but your wing loading is going to increase significantly. If it were my plane. Id stick with the 1.60 and play around with the setup (prop, fuel, etc).

Recently I saw a Great Planes promotional video in which they had the Extra torque rolling rather well. I suspect they were using the recommended 1.6 engine.