I think that there is no "good and evil" to be discussed here, there is jut simply two opposing forces and we are in the middle. In my thread ,"Why didn't the Vex kill us before the Traveler" I make the claim that the Darkness only killed us because it detected the Travelers light in us, had we not used the Traveler, it probably would have ignored us. Both sides use "pawns" to aid them. However what may make your claim is that I believe the Darkness represents entropy, the natural state of things, the Traveler represents order, an as such the two are destined to have an everlasting clash. The Darkness saw "order" in out civilization via the Traveler and it's natural reaction was to destroy that order. Basically as I said I think there is no good or evil in terms of the two higher powers. It's literally just a battle of opposing forces as nature intended for lack of a better term. If we were to watch a documentary about a gazelle in the wild, and the cheetah made an appearance to eat the gazelle, wouldn't you(not you specially but as a trained audience) label the cheetah as "the bad guy"? When in reality it's nothing more than predator and prey, as nature intended, nothing more, yet we can easily perceive it differently. But this only holds true until we get more insight on as to how exactly both "deities" operate, be it strategically, reactionary, etc.