It seems to me that they've been caught in a conflict of audiences. Their fans seem to want unbalanced gameplay, I mean, could you imagine the outrage if they got rid of commando? The super-powered SCAR? They want the level ups to not make subtle improvements to already good weapon sets, they want to become a fully kitted out badass by the top ranks, which is understandable to a certain extent, nothing's more annoying to spend time ranking up only to find that you've unlocked something utterly worthless, but to most of us ex-cod players who maybe loved COD4 but found that things got out of hand in WaW and MW2 alot of these new perks. No doubt, as game developers and therefore people who can (most of the time) understand what makes balanced gameplay, treyarch feel caught between those who want to become ridiculously powerful, and those who just want to play a decent game, and that's without even thinking what kind of pressure activision must be putting on them to adhere to what their most profitable market want, of course, keeping in mind that in this case, their most profitable market may not actually want a properly balanced game.
It seems to me that they've tried to please both crowds here, with the super powered perks and weapons that the cod fanboys want, whilst using said perks to create an air of chaos that anyone who's played a truly excellent big team game on halo an any point will tell you can make even an unbalanced game memorable and exciting. With the price mark up this time being a comparitively acceptable five pounds, I'm almost tempted to try it out, despite my mostly bad experiences with MW2 in the past. And the feeling of inevitable overpriced "buy our map packs, or be practically locked out of online" map pack spamming.