I'm not that sure microwave beams are not available today as energy transfer way. Do it have any resemblance to the electric teethbrushes charged by putting it on a nail in a base?Sorry, I am not expert in "microwave beams".
I just look for actually available energy sources
-I propose to look onto Conterrotating Propellers=in case of differential gear we can gainI am not fan of reduction belt
Unfortunatelly I don´t have possibility to test prop in wind tunnel.Have you calculated/estimated the drag from the feathered prop?, Wind tunnel?