Thanks for the suggestion. I have tried a few, DRG, Warframe, destiny, and some others, but that hasn't clicked for me unfortunately.
I really feel a game like Rust or PUBG, but with a massive pick up and play scenario with shared goals where everyone collaborates, would be a great game.
I haven't come across anything similar, as I think it would be something between a 3/4-person shooter and a full blown MMORPG?
I don't know, there are likely many technical complications obviously, but I feel there is unexplored terrain there.