I don't know how Pyro is going to implement a Perk system, it seems counterproductive to give good K/D ratios better planes. I think it should be based on bases captured, or ordinance dropped on target.
Anyhow, here are my ideas:
After closing X Bases, or so many pounds of ord dropped you get "chips" which you can redeem for rides in the following Ubers:
Spit XIV
Fw-190D
F8 Bearcat
Me 262
You should also get a "chip" every time you kill a building or ack in a Panzer, or capture a base in a M3. You need to avoid things like chips for killing other players, only strat targets of the enemy. Because otherwise people will open accounts just to get slammed down so they can build up other accounts. By making chips only earnable by taking or destroying enemy bases, you push the strat model while giving room for the planes that everyone really wants.
In keeping with the Aces High theme, Poker Chips could be used.
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