I know it is a bit of a harsh comment, but it is quite ridiculous in both realism point of view AND gameplay wise.
Currently, the Demo can equip 40mm grenade launcher, an RPG/M3 MAAW AND a nade of your choosing. For gameplay wise, this means you have 2 GL and 3 RPG round and 1 nade to spam. Not only that, if you tap on the supply crate, you can charge up your explosive count to 4 GL, 4 RPG and a grenade. In addition, if you happen to pick up another RPG, or 2 RPGs, then you can charge those picked up RPGs to 4 rockets each making 12 explosive shots possible. I had roudns where I was MVP just because I knew how to spam RPGs since the TTK is so high, that RPGs are basically cheese right now. I won't go into the realism part, since I'd expect it to be obvious.
To fix this issue I'd recommend something similar to the last game, but with the added features from the new.
- the grenade launcher: When GL is equipped on the rifle, the explosive slots are open to ONLY 40mm grenades, whether it be smokes or HE rounds. Each explosive slot will give 2 rounds of 40 mm nades. This means you can potentially get 6 in total, but you can mix and match with smokes/HE, making the role more versatile as well. In this case, the grenade launchers will be the same for HE and smokes.
Or alternatively, when GL is equipped, all explosive slots are disabled, but the GL round numbers depend on the ammo vest level (2 for none, 4 for light, 6 for heavy). I'd prefer the first option, but the later is pretty much identical to the previous game so I'd expect familiarity.
Side note: AK74 and M4 should also be available for GL launchers.
- The RPG: If RPG is equipped, IED and grenade launchers become unavailable. If another RPG is picked up, only the ammo will transfer, rather than receiving another RPG launcher. If a different launcher is picked up, it should drop the other one.
Side note: for Insurgents, RPGs should be cheaper due to it being a necessity for the faction to take down helicopters. Furthermore, RPGs may also have a home made HE variant ammunition for better infantry fights, but useless for helicopters or armoured vehicles. (refer to the game "Squad" with their RPGs on insurgent sides.
Role distinction: I think the grenadier and anti-tank roles should be separated if helicopters will still be a thing. I personally think that helicopters don't have a place in this game, as it looks rather off putting moving sluggishly waiting for an RPG or a nightmare to deal with. Without proper dedicated anti air system (whether it be a call in mechanic like Rising storm 2 Viet Nam, or a stinger is added (since they were used by the afghans) Helicopters will forever be weirdly slow to balance things, while still being a nightmare for maps without much cover, as it can spawn wipe the whole team if timed correctly.
This point is rather separate from the demolition role, but rather the observer/commander call in dynamic. Instead of marking targets with binoculars, why not use coloured smoke grenades instead? Whether it being thrown or launched by the grenade launcher. Then, the annoying forever babysit of observer/commander can be avoided, while the call-in mechanic becomes more risky (as you need to get close to pop the smokes if thrown, or need more coordination if launched), since it is already indicated with a coloured smoke anyways, why not make it a bit more realistic? I know this idea could be refined, but the current mechanic is not creative nor enjoyable.