Here, let me propose a reverse perk system, a blend of fantasy, logic, foolishness and perversity.
No, I didn't steal it from Beet1e, even though that description may sound that way.
Something like 5000 guys in the game right? If you judge by "lowest score" number.
OK, the top 2500 fighter pilots in each tour CANNOT FLY the five planes they had the most kills in for three months. Can't fly 'em at all. Not available to them. This is a rolling three month thing, each month adding five different planes. 15 verboten planes after three months, then in the fourth month the first five become available again and so on.
So every month the top half of the fighter pilots have to fly aircraft other than the top fifteen they've been successful in the previous three months.
Hey, they're the top 50%... Aces of the bases....shouldn't cramp their styles a bit. And the newer guys can fly whatever they like.
Kewl, eh? Elegant, even.
Only bad part is I'll run out of early war stuff in three months... we need MORE early war stuff.
Thank you and good night.