It looks like a cross between a Brute major's armor (gold Brute) and the Arbiter's armor with the ascetic cheek-blade things added on-- which is not to say that it looks bad; I don't have strong feelings for it one way or the other. I don't think it fits the Sangheili in the Covenant loyalists/Covenant remnant from Halo 4 better than the armor they had, which looked like regular Sangheili armor, just a little smoother, and they had less of it, befitting their lack of resources.