Fix the model or drop collisions. Period. Want realism. Model them for all aircraft. Model collisions accurately. Two opposing aircraft traveling at 400mph+ touch and only one dies? How can one person have a collision but not the other? Both aircraft should be damaged and in the majority of cases both would die or lose their aircraft.
The problem is you can't differentiate between damage caused by point blank guns, and the damage caused by collision.They are intertwined.