Ghosth is looking at this, I think, with an economists point of view. Let the market dicate the price. Since supply is infinite, the supply and demand would be impacted by a ratio of use and kills. I actually like the idea, but it would take quite a while (I think) to come to some equilibrium on prices and in the meantime, things could get ugly.
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That's why I think the player's fighter rank should have an impact on perks earned or received by the other player. Shoot down a player who is in a category better than you and you earn a slight perk modifier and thus more perks...and shoot down an easy newbie and your perks are decreased some amount. However, when the newbie gets a kill, he'll earn at a greater rate of perks and I think all this too will equilibrate so that the poor-middle players will have just as much access to an ME262 as the middle-excellent players.