I don't think there's any reason to get this personal, I prefer to keep it about the games.
G1G is right though, I think it's folly to consider any set-up overpowered, as there are far too many factors to make one omnipotent, and fact is that the game is supremely balanced to make it exactly like that. You will have less options in the beginning, but you can still easily make due.
Usually the people who start blaming the game are the guys who don't shoot straight, I don't know if that's the problem here, that's just going on experience. I always miss my ACR, but that's because it fits my style the best. I've scored just as good with an M4, an MG4 and a Scar, the latter two of which are pretty much as different as you can get.
Taste is always going to differ, but there's a reason why Modern Warfare 2 isn't about to be challenged any time soon. Balance, playability, functionality, precision with as little hassle as you're likely to get.