I think this is an outstanding idea.
AKAK, I see what you're saying, but the goal isn't to fool you, a veteran player. It's also not meant to hide GV's moving over open terrain.
The problem with GV icons as they are is every single enemy plane overhead gets a glaring beacon to you, regardless of whether you are using trees, terrain rises, or any other ground clutter to your advantage.
What turning off enemy GV icons would do would give a little more incentive to use terrain and vegetation as cover properly. It would also cut down on the impromptu attacks on GV's. What I mean by this term is when a pilot diverges from their intended flight plan because they see the bright red beacon of enemy GV's. They then go to strafe, bomb, or otherwise just buzz around and spot for friendly GV's. These pilots usually were not even looking for enemy GV's, they had a completely different sortie in mind, but the icons just draw too much attention.
It wouldn't take away from gameplay because, as AKAK said, those who are looking for enemy GV's from the air will still find them. I just don't think it's fair that players who take to the skies not even looking for GV's get a precise location and type, no matter what. GV'ing is about movement, surprise, and being able to avoid attention when it is unwanted. I'm not even a GV'er, and I realize how unfair it is to take away two of those three elements.