So here is my take on a lot of suggestions I'm seeing that people are attempting to use facts as a reason to implement said weapon.
The M320 GL - US Army Infantrymen can wield a M320 GL. It is not uncommon whatsoever for a 11 Series infantryman to carry a M320. So for that to be added in to substitute for the 203 would make perfect sense to me.
MK18 Mod 1 - No, never one have I seen an Infantryman with a Mk18.
If any marksmen weapon is to be added, the realistic direction is the Mk14. I have seen people with the MK12 SPR but thats in the Rangers/SFG area not Infantry/Parachute Infantry.
M16A4 - Almost no Infantryman carries the M16, the Army removed it a while ago and the Marines are now rolling it out completely, but if you wanted to stretch realism than yes a Marine faction carrying it would make sense.
Shotguns - Seriously? Maybe if this was in-your-face combat but even in real life I haven't seen people bring a shotgun to a mission that would even suggest CQC.
In terms of Sniper Rifles, I don't really care. I have never touched a sniper rifle in real life and am never gonna touch a sniper rifle in Squad.
The M240B is already on the forum post it seems so no need to go into that.
Optics - I'm sure you guys have gotten Optic request up the wall but here is the crucial optics for the Infantrymen
I had a C79 on my SAW for a while.
I wasn't trying to throw anyone in the spot, if anyone wants to have a conversation about these suggestions feel free to contact me, I am always willing to answer questions for people.