I think part of the problem, and I found this with CoD4, is that the better you get, the better stuff you get - so the "pros" have all the advantages and the new chaps are at a disadvantage. Surely it makes more sense, balance wise, to handicap the best players and give a leg up for the worse ones? Simple enough to impose - instead of getting newer and better guns as you level up, your choices become more limited until you are armed only with a blunt butter knife. Plus, after a while, after everyone who wants it has got it and some time has elapsed so that everyone is pretty much top tier and fighting one another with butter knives, they'll get bored and turning off the servers won't be so much of a heartache