Since bungie is cutting out content and sticking it back in as payed dlc i am sure we will hit that spot where it comes to some alliance. Think about the game so far, you never do a mission where you have to protect/follow/find or fight together with npc's. Almost every shooter has this element and in the vidocs there are these kind of mission (ok we only know about the one with "Crow").

Unlikely. Most of the focus of this game has been, "Play with friends," and as long as their are people to play, Bungie will not want to resort to filling in the gaps with NPCs.