The information that is there IRL but cannot be seen in AH even with icons is the most important one: attitude of the aircraft.
Range counters - too much information. Light color to identify exactly who is the enemy - too much information. Perfect ID even at 4k (distinguish even very similar planes) - arguable, ihmo a bit too much information. Unable to see the attitude of the aircraft, easier to see than the other information IRL - impossible in the game at >1000 yards.
For GVs... I catch myself flying low to be within icon range of nme GVs to be able to spot them quicker. Maybe remove them, and make the GVs throw up dust when moving.