Quite simply to return AH to a sim and lower it's "game" status, killshooter should be abolished completely.
Since most of these are because of poor SA, the person zipping in front of you should take the damage. As I've pointed out before, someone coming into a battle from below and behind is at fault. The friendly pilot can't see someone coming from that location. So, if a friendly shoots you, you die with no penalty to the shooter. The only exception to this should be in totally friendly situations. Such as in an area where no enemy are present. Even then the killshooter is questionable for the sake of realism.
If someone clips your wing (friendly or enemy) you both die if the damage is severe enough. Mid-air collisions should affect both planes no matter what the situation. In other words a big BOOM for both pilots.
Runway collisions should also be enabled. There is no way on earth 25 planes could ever take off and land all at once, using the same runway on an airfield. They would have to be spread out over time. This business of a plane passing through another plane during takeoff is a bunch of non-realistic balony. Some sort of tower clearance for takeoff needs to be implemented, or the pilot needs to decide it's clear for takeoff. If he's wrong, he'll learn quickly that ground crashes will kill both him and the one he hits.
Anti aircraft guns should affect both friendly and enemy planes. AA was not and is not selective about it's targets. If there are friendly planes in the air while it's firing, the odds of a friendly being hit are the same as hitting an enemy plane.
Anyway, if all of these were introduced people would quickly learn the consequences of poor flight habits.