The term "Light Machine Gun" is very broad. Encompassing a range of machine guns all designed for very different things.

The game started out with 3. The M60, the RPD and the DP-28. The M60 was designed from the German FG42 and externally looks very similar. It was designed to fire from the shoulder and while it got it's nickname "the pig" for it's weight it's relatively light compared to many WW2 counterparts. The RPD was designed during WW2 for the new mobile warfare. Barely utilised in that war. But it was very light for a belt fed machine gun and could also very easily be fired from the shoulder. Thanks to the intermediate cartridge it fired. The DP-28 was an interwar design opting along the lines of the French and Czech MGs at the time. The main difference being a larger pan magazine instead of a traditional box magazine. While nobody envisioned firing it from the shoulder soldiers did so anyway and walking fire was a concept at the time of it's design. Though it was rather long for that.



But now we have much larger machine guns. The M1919A6 was a modification of the M1919 medium machine gun to try and make a light machine gun. It was extremely heavy and had no real places to grip it so a carrying handle was added (which the game neglects to use but didn't in RS1 which is very odd). The shoulder stock was designed to make it very easy to fire from prone. But it makes it very tricky to bring up to your shoulder while standing. The gun weighed 15kg and the 250 round belt 5.7kg. The M60 for comparison is 10kg.



The upcoming MG34. Heavier than an M60 by 2 kilograms. The M1919 was trying to copy the role of the MG34. Which was a weapon one man could easily set up anywhere and start shooting. But you'd get into a bit of a pickle if someone came up behind you.



The upcoming RP-46. A modified DP-28. But 2.5kg heavier than a DP-28 empty. Due to it's heavy barrel. Overheats slower and has less recoil because of that but the gun is of course much heavier. Along with having more ammo.





There's also the L2A1 and BAR. But they were rifles turned into MG's. The Automatic rifle concept.





Anyway. I think with these new bigger MGs we should seriously consider whether or not we should be able to Aim down sights with them. With the 3 described above I no longer think that we should. Hipfire only unless mounted. Or potentially a "braced" mode. Where you don't aim down the sights but your character moves the gun into a better position to fire when you ADS. Lowering movement speed. Similar to folded stock weapons.



I also feel that the MG34 and RP-46 would simply out compete both the DP-28 and RPD. Belt fed, full sized round and the MG34 has the fire rate. If both could ADS shouldered why would you use anything else?