That's really the trouble though. What's too much - or what's not enough...what's irritating, and what's acceptable, all varies from player to player. So no matter what they do, there are always going to be people who aren't happy with the balance. My personal experience though, has been generally good. I've only come across a couple of quests that became absolutely miserable with more than one player doing them. But that says more about those quests needing to be tweaked, than anything against CRZ.
This might sound a little odd - but unless you're the type that generally likes interaction and compensating with/for other players - you're not likely to walk away with anything positive for the time being - especially if you're on a lower population realm. There are just certain things the developers will need to do to make the game behave in the way they intended it to - regardless of whether or not the players enjoy it or not, and CRZ is one of those things.
I'm pretty sure they realize that it's going to cost them some subscriptions as well. Especially from Wrath/Cata babies, who have likely never seen the 1-60 zones so full of people. But, for better or worse, they're running with it.