Foam - what a wonderful tool--
We purchased a grundle* of Depron in various thicknesses and spent the morning out flying various permutations of one design.
They are all between 6-8ozs . wing loadings 4-5 --4-3 oz sq ft
The only positive finding-once again -is that given calm air - you can't beat lower wing loading .
Even moving cg around -- the model (four of em ) with lightest loading --was most controllable when flown at low throttle (I guess we should call it a rheostat) and pulled and held right at the "stall".

all were flat foam -all braced the same all same scale etc..- so no airfoil variables - just wing loading differences.
Too bad the boys who pi--ed all the money away on the OSPREY didn't have a a few hectares of foam and some latitude to use their imaginations.
I think the government approach is hectares of money and no imagination.
* great big bundle -- old western folk expression