There should be a custom games playlist/lobby, players in the lobby choose to "host a game" (pick gametype and map that anyone in the playlist could join) or "search for a game" (join a random party of other people playing a custom game)
Parts of helmet incorperated into multiplayer HUD like halo 4's campaing. Feels so much cooler to land a big jump and see your helmet shifting around you
Also make the rogue helmet look like halo 3's helmet instead of looking like an elite helmet from halo reach