What he said, Elites playable in multiplayer. Arbiter. Return of the SMGs, the Brutes and their weapons, even better multiplayer maps. A Forge with 2 or 3 Forge World sized maps with different themes (covie, forunner, human) or another forge world with all three themes. And of course, A skill based rank system. And our classic lovely playlists like Team VIP, MLG, Griffball etc, in the game since releaase.