That's Halo… race to the ship before the ring blows. But yes. The Vex and the Stranger will be the main story line, I think. I do think a greater Cabal enemy is going to play a role now that we're actively thwarting something they're trying to do on the dreadnaught. I think the Fallen may become allies or loose allies at some point once the traveller has recovered sufficiently and accepts some of them back to fight off an even greater Hive god.