If span is not constrained, but stall speed is, then increased AR allows lower area. Correct me on that, please. Or.... Increased L/D allows lower area? Either assertion fits the facts if you look at wing area on modern hang gliders. http://www.moyesusa.com/products.html These are all roughly the same planform, a flying wing. The Malibu has a thinner airfoil and much more exposed structure than the other 3, more twist, so if you prefer to keep it as oranges to oranges, just consider the 3 models with the buried cross spar. None of these is as efficient as an ideal wing. Laminar flow is very limited, as the first seam in the upper surface trips the flow, if near imperceptible span wise ripples haven't already. The exposed pilot can be more than half the total parasitic drag. However, as a side by side comparison, those factors are about equal.