[Information confirmed on Halo Waypoint through Frankie via twitter or something else]
Armor Lock will not be returning.
Custom loadouts will be more like Gears of War actually. You get a choice of your primary and secondary (a small choice . . . you don't spawn with sniper and rockets) along with your grenade type and armor ability. There is a fifth option which I am currently assuming is armor modifications. I actually like the new system because I can mix the game up a little by switching between maybe a DMR and BR (although you have to unlock the BR).
Not all playlists will be featuring custom loadouts. There will most likely be a few classic-y playlists with regular starts.
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