I don't think it is nearly as unbalanced you think though. And this time they've added "Death Streaks" so that if you are getting your butt kicked you get a boost to help even the odds. For example, the Copycat Death Streak allows you to 'steal' the weapons and perks of the person that just killed you (once you die again though you get your 'old' weapons back). I've even been getting my butt kicked so much once that the game gave me the Last Stand perk even though I was only level 3 or 4 and you don't unlock Last Stand until level 39.
The matching making typically does a pretty good of keeping people of similar rank together too. Personally I really like the custom load outs so you can tweak your gear for the different game types (like for Domination I load up on explosives because I know people are going to be more stationary as they try to control the select areas of the map).
I got the game a launch and am only a level 31 or 32 but I can hold my own against people that are 20 lvls above me. Getting the nicer gear is sweet but it still comes down to how fast you can recognize a target, sight your weapon and bring him down. This version also has a lot more chances to earn XP so leveling up is easier than before.
Lethal