As far as "The Stranger" goes, here are my thoughts: There is a known faction of Awoken ruled by the Queen and her brother. I believe The Stranger belongs to an Exo faction. this could explain the Stranger's apparent loathing for the Vex. The Vex being another Machine based race, but bent on destruction and re-writing the universe. I'm not saying all Exo belong to this unknown faction (just like there are many Awoken guardians). Many wonder why, when playing an awoken, that the queen doesn't comment on this. But it's because in her eyes you are NOT Awoken. You are a guardian. Just like the Queen, the Exos need a Guardian for a the next phase of their plans, so the Stranger is tasked with finding one. You. As for their allegiance... Well, some of the Stranger's more ambiguous dialogue leaves that open to interpretation. P.s. The Exo faction could be "The Deep Stone Crypt" mentioned in some Grimoire Cards but that's pure speculation. Just my thoughts on the matter. let me know what you think!