If you've got an American MG it's not hard to cut down 6-12 'Banzai-ing' Japanese before they even get into an objective... assuming you have a decent position and they're not right in your face.
The most annoying part of the MG is finding a place to use the bi-pod effectively without bugs, and having to shift your position and reacquire the sights every second, especially in the heat of battle. Being able to crouch fire the japanese MG's using the sights would make it far more effective and much less tedious to use.
I hate people who complain about 'Rambo-ers.' shut up. I cut people down with the (Japanese captured) 1911 at 100m, when I'm MG class, because hip firing is not very effective or ammo efficient, IMO. You gonna cry about that when I take out half a dozen guys with a 1911 or a suppressed 1895 nagant too?
If you can't kill a 'ramboing' MG'er who's hipfiring your reflexes and ability to aim are probably just poor.
Japanese type100 is garbage. I'll only use the 1st tier one, but I've found the bolt action to be far more effective at all ranges, if you can aim.
US has Trenchguns, Thompsons, BAR's and Garands (on top of their LMG), that's a F*&*load of firepower to stop a banzai charge. Even with a health buff, automatic weapons will cut down the Japanese easily, especially if they're moving together in groups.
Honestly, the 'balance' isn't that terrible, with a good Japanese team, but I'd like to see shoulder fired Type96/99's simply because it's so hard to find a good location to use the bipod without 'cannot deploy here' and other annoying issues.