I would like to see third person as a custom option in the reach title update, helps appreciate the armor a little more plus it looks fine in theater.
As much as I would like having a 3rd-person perspective to look at my Spartan, I do not think it is necessary. If one wants to look at the armor in third-person they can just watch a recording of themselves in theater from a third-person perspective, or they can just look at the armor in the armory menu.
Having more options can be fun or even beneficial, but I do not see the point other than to look at my Spartan and perhaps have a “Gears of War” feeling every once in a while.
Never gonna happen ever.