Allow me to disagree here. I've been flying this plane with a DLE 20 and it sure flew it well. I would say the DLE 20 is right in the MIDDLE of the power range, flies comfortably, climbs well but not unlimited vertical neither speed demon in a straight line.
A 17x8 2-blade is faster than 16x8x3, so before you cut the spinner give it some thought.
That said, I am going to experiment with a 26cc MVVS which should swing a 17x10 - 18x10 for higher top speed, but this is more curiosity than necessity.

I'll post a video later with the DLE so you can judge for yourself.