You got me there
Naksiloth is obviously half-right here. They were scared they would have to make my idea, the firework rpg, and were so spooked by the concept they rigged the vote they themselves started. The LMG removal was but a ruse in an attempt to trick people thinking about that instead of my firework rpg. It's so obvious this was rigged! How could you, IJC!? :]
M60E4 had like 30 votes before removal, because someone in the entire team simply forgot to tell "LMGs are not allowed and they suck, you're all CoD loving idiots and no way in hell we gonna balance that".
Now which theory I should count in and credit? One, you had something prepared already from the leftovers of ZED mk2 concept and freezer gun seemed like a good idea; two, someone forgot to say LMGs are not allowed before M60E4 hit 30 votes.
A gun with ~100 bullets becomes Body Shot: The Video Game.
All you end up with is an assault rifle with an inflated bullet count and fire speed with low bullet damage. That's not fun or enticing gameplay. Post your set of balances for LMGs in a thread as a mod for the vanilla game so people can actually try it. Simply saying "I did it and I'm really good" doesn't make anyone really believe you (or care, for that matter, since anyone can say "I've balanced that").
We already have a DLC/unlock weapon with 50-62 bullet count for mando, and it's still far far away from making the game a bodyshot fest. If it makes the game a bodyshot fest then it should be removed or at least get called as a P2W weapon on the community. Nope, Drum magazine Tommy guns are not flare revolvers.
Inflated bullet count; yes. Reloading in the middle of a ZED time is annoying and LMGs have plenty.
Increased fire rate; nope. They shouldn't possess anything faster than a SCAR (600 rpm) as M60's rate of fire is very close to it 500-650 rpm. It can be 500 rpm and no one would complain.
Reduced bullet damage; nah. We don't want another pea shooter but an expanded magazine, higher recoil, high damage light machine gun.
Ofcourse there could be draw backs to that, like just an extra drum magazine of 100 (200 base 250 with mando bonus) thus not allowing you to trash clear that effectively, longer reloading sequence comes in mind. Also since it's a large and long barrel rifle, it can push you back when going full auto unless you're in a crouching position.
As for balance, heck no, you're beating a dead horse there and it'll be a mutator, not even part of the official game. We're playing a coop game to kill clones, it's not a competitive play. No one care about M99's current balance. It was too powerful and devastated Crossbow on many areas of gameplay and it got a price increase; fair and square. Now no one uses M99 besides Patriarch wave.
That's what will happen with the LMG, if it cannot be balanced it will be pushed over to the Final Wave, (or server admins will ignore it) yet we still get what we wanted. Will anyone out there will still be left caring about KF1's "muh balance" when KF2 come out? All in all, if it's a mutator let server admins decide if it's balanced or not.