Hello there!
I have some suggestions for MP missions to make them more fun and interesting:
1. Battleship hunting missions
Make pirate bases offer missions where you go and destroy house battleships, like assasinate a fleet admiral or such. Awesome for group missions.
2. Tradelane disruption missions
Pirates offer missions where you have to attack a convoy or such, like the missions where you have to tractor in cargo, but the ship that drops it is a train. With large defences. Another group mission.
3. Anti house missions.
Make houses attack each other, like Liberty have covert missions against Rhineland patrols.
Any comments?