For what it's worth, I found the AHIII formula, before the 'quadrant' pretty perfect. GV should be hard to find from high flying planes. Planes are fast and cover a lot of ground. flying low around a town or base seemed perfectly appropriate.
They were find-able, but it was perfectly difficult. Airplanes had too much advantage when GV hunting, and the change in icon range and the new trees created the perfect balance.
Its my opinion that the GV fights are better, because the planes don't come out and end the fight so easily. So people are willing to invest the time in GV missions.