Throw out the perks altogether. Or rather revise them to be what they were intended be:
1) Give 100 perks at the start of each tour for anyone under 100. If you have over 100, you keep what you have.
2) Allow perk points to accumulate slowly for time spent in the air, online, If no control input is given in over an hour the perk counter stops untill input is given (this stops the park it at a back base and leave).
3) Give perks for damage done, not just things destoryed, or aircraft killed.
4) Give perk points for makeing and takeing part in missions. (A mission would have to include at least 3 aircraft, and be at least .75% filled to qualify for points)
I DON'T LIKE PERKS the way they are.