Theory ; Oryx true intentions is freeing us from a fake god.
*long read ahead*
As we all know, the Hive and Oryx are extremely devoted to destroying the Light.
The way we see the Light, is the way they see the Darkness. It must win the war with the Light, so that the Darkness can reclaim the universe.
Now, the Traveler gives us harmony. Awoken and Humans do not really like eachother, yet Guardians of both these races fight with eachother against our enemies, in [b]harmony.[/b]
The then Proto-Hive however have known only conflict. They live short lives, and have been at war a big portion of their existence, and living as prey.
Through Darkness they gained power, which meant that they could free themselves from fundament and grow into the powerfull race that we call the hive.
Simply put ;
Darkness shattered their bonds so that they can grow. Hive have learned from their experience that the Darkness released them.
Very similar to the Light and Guardians.
They know only conflict and Darkness, and see mercy, forgiveness and compasion as a form of weakness, which is why Oryx pronounces "Your travelers light-.." with a tone of digust.
Us humans see those terms as generally good.
Now, The Hive see them as something bad. And because they have learned that those things make them weak, they see the Light and its harmony as a weakness.
Which explains why they are so extremely devoted to destroyed it and "freeing" the galaxy of it.
Now here is the fun part :
Another line of Oryx is "The Darkness is a gift, let my will [b][i][u]set you free.[/u][/i][/b]
He wants to free us from the Light and join the Darkness, so that we are no longer bound to harmony and seeing eachother as equal, and we can grow stronger through Darkness like the hive did.
If this is correct, then the Darkness isn't truly an evil concept, it is just total freedom and no rules, but we see it as evil because its opposite is what gave us so much and because conflict only gives us grief and pain.
Another theory to add is that the Traveler makes us see things differently, which is why the hive have names which we accompany with good things. (Knight, Wizard and Acolyte.)
TL;DR : The Hive and Darkness wants us to live free of rules and it isnt all that bad.
So what do you think? Like my theory, or not? Support it or want to disprove it is welcome in the comments below.
Sorry for bad english, if that is necessary to say.
/discuss
Did you forget the Hives entire existence is in accordance with the sword logic and they strive towards the final shape of the universe, where one species is left because it has killed or outlived every other one? This is why oryx kills everything in his path.