For dead air, aside from thrust, prop efficiency, disc area, etc., the high-A/R wing is absolutely the best thing: more lift with less induced drag means that there is less energy lost in tip vortices. Its disadvantages mostly disappear with the gusts.
I think we sometimes confuse the flap thing with weight. Lighter planes are better - within reason - in still air, since they require less lift and will not encounter gust upsets. There is a limit, though, which I proved in the notorious post that provoked displeasure at its first-month high school algebra symbols. The point is that the deflection of flaps is dependent on aircraft weight, and the lighter plane needs less flap deflection. It's not the flaps, but the lift required that makes the difference. You can get that lift throught higher angles of attack or greater camber (flaps). Both will create the same vortex loss, not splitting hairs on parasite drag from interference.
The equation for induced drag (for elliptical lift distribution - which is 'close enough' here) is * (See Below) Di = CL2/(pi x AR) or simply KL2/(AR).
CL = Lift Coefficient; pi = approx. 3.14159...; AR = Aspect Ratio; L = Lift; K = a constant determined by air density, speed, chord or area, etc.
*Edit: Howard (below) is correct: I should have written Cdi instead of Di, because I gave the expression for the induced-drag coefficient. This makes the weight and span of equal importance - span loading, as Howard says.
This says what you need: simply, *(Edited for clarity) For constant area, the greater the lift coefficient the greated the induced drag and the greater the aspect ratio, the lower the induced drag. **edited to eliminate an invalid characterization: Of the two, lift required (due to weight, inertial mass) is hardest to handle, while the aspect ratio is easiest to increase. With lower induced drag, you get smaller tip vortices, which means less wake turbulence.
Wing plan form is also important, and tip shape should be optimized within structural limits. Of the standard shapes, the elliptical chord distributions, like on the spitfire, T-Bird, etc., have the least tip losses for a given lift. There are others, pictured in other threads, which are a bit more efficient. If we were concerned here with gusts, their aero centers are advantageous too, being significantly inboard (at 42% of the half-span) of those of the most familiar configurations, thus reducing lateral upsets. Although that's off-topic here, I've included a drawing below to show the taper necessary to have the same inboard lift center as an elliptical wing of the same area and aspect ratio (accuracy limited by the MicroSoft Word tools - not CAD) - just FWIW.
SK
P.S. The slightly thinner air foils are probably better in windy weather, rather than calm.