To turn a normal 15x8 prop at those rpm, you need 11hp. Period! The blade tips will be supersonic though, but that seems to bother you none.
If you meant some kind of single narrow blade toothpick prop, please say so instead of badmouthing other engines than the ones you like best.
In standard configuration out of the box, I know of no gas airplane engine that outperforms the 26cc MVVS, sold in the USA as evolution engine. You did not convince me one iota otherwise. Using the data you did does not improve things being beyond the realm of the normal two stroke engine.
Please provide data to back up your claims.