The main thing that I would recommend implementing with the new system is for the magazine loot table to factor in all player's perk adjustments, perhaps with its own slider akin to the kill xp share range.
So let's say you set the range to 10k. If I go looting as an SMG user, I would also find magazines suitable to my Shotgun user friend who prefers to stay near the base and gather raw resources. I may find less of my own because the quantity would stay the same, but it means my friend doesn't fall behind just because looting isn't his responsibility. Or we can just set the range to 100, and that way we can let your speed looter do his thing while still getting our cut.
Perhaps even better it could just be a toggle in the social menu that can be flipped on the fly. Tick on "Enable Party Loot" and everyone who also enables it will be factored into a communal magazine probability table. Then if somebody needs to catch up or just wants to speed ahead a bit more they can drop out (with an automatic party alert) and take on a few POIs to get their ranks up.
The fewer people you play with, the more work each individual has to do. If you play solo then you need to be a jack of all trades to an extent. But in multiplayer players often divide the responsibilities, and some end up looting far less than others by choice. I think it's a fair assumption that every play group will have somebody looting, but the new system assumes that every player will be looting, which is not always the case and a scenario that should be accounted for.