RE: two airfoils on one wing
Iron Eagle, you have a `reverse delta' for want of a better term, tip stall will not be a worry. with normal deltas the wing has plenty of sweepback for stability (works like dihedral) but I see yours has forward sweep. Probably not a huge problem, but I would make those tailplane/elevators into tailerons for roll control, rather than those tiny ailerons.
Evan, WB#12.