Crap, why are you guys complaining about unbalanced game when you have higher KD ratio than me ? I'm not bitching too. I just need more time to work and play.
Once I figured out how to fire the standard assault rifle with the dot sight at long range, everything was good.
Basically, if you tap the trigger, you get almost zero recoil. You can fire pretty fast just by rapidly tapping the fire button. At long range with the dot sight, you can be very accurate and deadly. The other big thing is to learn not to use dot/iron sights unless you're far away. When you're mid to short range, just shoot from the hip. There's enough lag compensation and aim assist that you really don't have to be very accurate. Just fire short bursts.
That's how I've managed so far. I haven't played any maps with all the badges unlocked yet, and once the sniping, tanking and rockets start hitting me, I think my KD will drop.
Oh, and a quarter of my kills are head shots. Those drop guys way quicker. I blindly sniped a few guys with head shots using the standard pistol at pretty long range, which must have pissed them off. It was an accident, but the kind of accident I enjoy.
Oh, and don't be too aggressive. The shooting mechanics are not suited to run and gun, despite the obscene damage some guys seem to be able to soak (not head shots though). Find the group of guys that are stupid enough to charge all the time, and stay close, but hang back a little bit. Clean up their garbage and look for guys at long range. Play support, not the hero. Of course, don't be a total KD whore, actually try for the objectives, but attack in a controlled manner.