Couple things that I want to point out.
#1 That comment earlier about the grunt taking an engine apart and putting it together again is incorrect. That was a huragok. That floating tentacled thing.
Also about about the wraith not having the power to fire very far and having very little power, I remember reading somewhere that it is supposed to have an ability to settle to the ground and essentially entrench itself so it can fire more rounds at once and have more power to fire farther without as much recoil as it would have when its hovering.
The past is history, the future is a mystery, this moment is a gift. That's why it is called the present