Although I will happily espouse the virtues of Star Trek Online, the multiplayer element of this MMO is very much optional. The central mission arcs are all solo friendly and although you can play through this content in a group, there is no major incentive to do so. The only times I have grouped during standard PVE content has been to help another player new to the game and when replaying a specific mission for the rewards if offers. The latter can be done a lot faster when grouped. The space and ground queues that are available at level 50 are designed for 6, 10 or 20 players but again the multiplayer aspect of these is somewhat arbitrary. Players can either join a PUG via the group finding system or set up bespoke event themselves with friends of fellow Fleet members. Beyond that there is no compelling interaction between players.