A while back (45 years ago), Orbit showed their newest small radio in a full bodied Ringmaster. The only modification was that the wing chord was reduced along with the addition of ailerons and a rudder of course. It was powered with a .15 sized engine (as a CL model it used a .35), but most of the drag is from the control lines to the airplane.

I built a CL combat model called the Guillotine into a RC model in 1972 that flew very well. Mostly had to add a couple of vertical stabilizers onto the booms, and find room for the tank and radio. It was a bit smaller than the Sig Wonder, but similar in configuration though the elevator was like most combat designs with no fixed horizontal stabilizer.