RE: Propellers
Thought so, you can try the 2-blades 10x6 or 11x6 this gives you more air speed. The 3-blade on the engine now has only a pitch of 4. Remove also the Flywheel of the prop nut - this is only good for low idle - but hinders performance.
there is a very interesting threat in the ARF section about that airplane and mods...