Maybe we can give this a go when its released
PWCG 6 has been in the works for about 8 months now. This is a significant rewrite of a 100K plus line code base, so it takes time. However it's getting there. Hope the alpha for coop can be released in a month or two.
PWCG 6 will allow many participants in any squadron flying for any side. It is coop and not MP. Access is controlled by a host who will run the campaign. The missions will be PWCG missions in a PWCG campaign, just with lots of humans flying on all sides.
This format accomplishes several things.
Players will be known and hopefully trusted by the host.
Players will have an incentive to fly as real pilots did.
Lose your virtual life and you start over as a new pilot.
You can have multiple personas in the campaign.
Choose to fly fighters one mission and dive bombers the next.
Have something to do if your main pilot is wounded and cannot fly for some time.
Great for squads that want to conduct a war.
Great for a like minded group of players who want to fly missions in a larger framework.
If you want pure coop (not human vs human) you can still have it at any level you want - everybody in the same squadron or flyers in different squadrons on the same side.
If you want to fly against your friends then you can do that as well.
As far as I am aware nothing like this has ever been done before (I could be wrong). Flight simmers have had MP for dueling with humans and single player for campaigns, but never campaigns with lots of players.