I see little comment on weight and loading -
The theory stuff is fun reading.
My practical experience on this same problem showed a couple of things:
1 youjust can't make a 1/2 a model too light - impossible - too fragile -yes -too light no.
shoot for 10 ozs.
make the wing a thin as possible whilst holding strength
The lower AOA possible with reduced weight reduces induced drag.
Thinner wings have more lift -at lower AOA-BUT nasty drag at higher angles.
eliminate all 90 degree intersections with wing to fuselage -make the wing fair into the top or bottom of fuselage
save weight wherever possible.
Use a low aspect ratio wing -on a 1/2 A - the RN is so small that the extra chord helps.
This setup will land slowly -as you can pitch it as req'd to induce drag-
a more aft c/g can be used -but elevator control becomes more critical-
with a aspect ratio of 3-1 you should be about right for *****g the setup.
One of the best full scale designers -ever - was Steve Wittman- designer of the Buster and Bonzo and Tailwind -etc..
The EFFICIENCY in the designs was what made em work -
Look at em and you will see the best layout for a good 1/2 A