I've always envisioned a system integrated multiplication interface of sorts for c-bills.
Basically, losing team gets either a damage multiplier or c-bill multiplier once they fall so far behind. Each hit or contribution would net a higher than normal return than normal against the winning team to try and level up the playing field a bit. Once the losing team catches up beyond the score threshold, c-bill accumulation or damage dealt would return to normal levels. If done right, it will keep the game competitive without trying to make a game dead even. the losing team would only get such a multiplier when the are losing by a certain amount (IE percentage of total score) and not anytime they begin to lose. This should be an optional setting for each server; similar to league rules for ejecting and the like.
I also would like some sort of system for personnel scoring vs. time left in game. This would essentially give a player help when they join a game halfway through or later, when most of the players are in expensive mediums, heavies, and assault mechs. After so much time has expired, any person playing or still playing that is below a specific rank (IE PCM/MSG) gets a score multiplier up until reaching the rank that is set, after which scoring/damage/level of derp/ returns to normal.
C-Bills @ rank and cost of assets can remain the same and the top tier guys wouldn't get extra help or extra starting C-bills, just the little weak ones, and only when they really need the help.
But I have no idea how coding and things of the nature of game design work, and so I don't know if this is possible, if at all, in Cryengine using Crysis Wars as the base...
Although I do second the notion of adding an extra rank or two somewhere in the middle of the pack. I always get to the point where I rank up and I'm at like 55k or 75k and think "I wish I could grab that 60k or 80k mech" and then I rank up soon after and I'm like, "Screw that mech, I've got 65/85k now, I've got THESE mechs to choose from.