Seriously. Do it. RoF of 600 for a minigun? That's like 1/10th of it's true speed. Terrible. It makes it one of the worst guns out there. A weapon that should be TTK king it laughably bad, when 99% of the time you're outnumbered and you want to kill things fast.
Seeing as how the sole reason they implemented those limits in the first place was because the devs said the high fire rates were causing disconnects and lag in MP, I highly doubt they will be completely removing them any time soon. They also just recently doubled (increased) the fire rate due to optimization, so that's likely the best we are going to get for the foreseeable future now.
Just have alternate weapon tables for singleplayer then. Singleplayer should suffer because of multiplayer.