Any gun with a fire rate of 650 (or even 700) just feels clunky to shoot with. I believe that the fire rates of some of the ARs and carbines should be buffed so that they can more effectively compete with the SMGs and PDWs in the current meta.
Even if they deal high damage, they will still get beaten by the MP5 and P90 because faster bullets shred through opponents
(I am not calling for an SMG/PWD nerf, as we have already had many of those by now).
Additionally, ARs with a high fire rate, like the F2000, feel like pea shooters, farming hitmarks over kills.