Here's a DLC idea: you are required to do a story bounty on Mars, and your in orbit, until an animation shows of you crashing. You barely survive, you're ship is unsalvageable, and Dinklebot is nowhere to be seen. Later on this hot, dead planet, you discover you are on Mercury before the Vex. Your Guardian has somehow ripped the space time continuum and now the traveler has not been discovered, there are no guardians, and The Darkness is arising and trying to bury the Traveler under Freehold. This is also where the Exos were born, a prototype of The Vex. It will give closure to the story, show backstory of The Stranger, and lead to the events of Exos going bat shit crazy and joining the Darkness after destroying the Tower from the inside out. It will also lead up to the final battle between The Darkness and The Guardians.