User blog comment:B1littlehero/Speculation of the Origin of Species/@comment-160529-20140611064056/@comment-7622429-20140611124925

Well, the Traveler apparenty became dormant many centuries ago to ward off the Darkness, but that event plunged Humanity into the Dark(not ness) ages. And now the Darkness is back. This time, the weight of responsibility falls on the Guardians. So, no, I DON'T think the Traveler was evil. In fact, it may have ushered Humanity into the Golden Age specifically to combat the forces of the Darkness.

Also, I agree that most of Humanity's enemies aren't really tied to the Darkness as its own personal army. Specifically, the Cabal and Fallen seem to be, as I've said below, "guns for hire". Basically, they have their own goals, but are willing to heed the Darkness' call for aid to eliminate the Traveler and Humanity. The Hive are almost certainly the REAL army of the Darkness, unrelentingly loyal servants to its cause, and in turn, the Darkness gives them the powers to enforce its rule.

The Vex are a whole other story. Due to their nature as time-travelers, it's difficult to pinpoint whether they came after the current time period in Destiny, or from the distant past. Both are plausible. However, I do believe that they are more closely connected to the Darkness than the likes of the Cabal and Fallen, but not as much as the Hive.