gonna get platinum pretty quick with the M40 and XM22
The ARs are pretty well balanced, usually have a tough time choosing between the M16 and AK, the M14 eats through its 20 round mag too fast to be as versatile. Although I think the AK is ultimately best overall
As far as the LMGs, I'll take the XM22 hands down. PKM/M60 power from the main game, but handles like a SAW with its accuracy/ROF and 200 round box. M60 is useful against Hueys, but that's about the only time I'd really want it over the XM22. I like the RPK's ironsights for longer range engagements but overall its matched if not totally outclassed by the XM22 and M60. Don't get me wrong, I don't think the RPK is underpowered, but I think the XM22 could be a potential candidate for nerfing if they ever patch the game. There will be situations where I'm using the RPK or M60 and I end up wishing I had the XM22 for its 200 round mag.
And for the SMGs, well the PPSh seems like the obvious first glance winner according the stats (and most Engies I die to seem to carry it) but I favor the Uzi because it handles almost identically to its main game counter part (but is more powerful). Mac10 is definitely a let down, I think it should have a suppressor, otherwise it feels way too lackluster and inaccurate to be chosen over the other options.
M40 is also the hands down winner for snipers. Its one-shot-kill radius is significantly larger than the bolt actions in the main game, I could see this being nerfed a bit in the future. The semi auto snipers definitely seem too weak considering they're practically direct clones of the T88S from the main game but with different range scopes (IIRC the M21 has a shorter range scope which would make it better for closer quarters while the SVD has a longer range scope, this is assuming you don't choose 12x scope perk), in fact with a slightly higher recoil amp if anything these rifles are actually worse than the T88S. I can only guess that DICE thought there would be a lot more players who couldn't play without their ACOG crutch and thus there would be a lot more people using the M21 and they didn't want to make it too powerful against all the other people stuck with iron sights.
The 1911 is identical to its main game counterpart and the TT33 is a clone of the M9. Not quite sure what to think about pistols being no more powerful than pistols in the main game, they definitely take more of a backup role thats for sure. I suppose their vast superiority to the other guns when wielding from the hip is what merits a neglect to up their damage, they could become too OP that way.
Flamethrower is neat, but I really hope the novelty wears off soon. Too many idiots run around with it when they shouldn't be if they're trying to help the team.
no, nade resupply rate is faster. there have been others complaining of this too.
M79 resupply time is 10.5 seconds just like the 40mm, but the M79's reload time is slower, so it has a slower ROF which means those grenades might feel like they're being resupplied faster because you can't deplete your supply as fast...
as far as hand grenade resupply times, I'm not sure what it is in Vietnam but in the main game its 7.5 seconds and for the most part resupply times of similar weapons between the two games have felt the same to me. I really think the increased grenade spam is due to the increased number of people carrying the double grenade perk