Theres one thing that can make the halo 4 campaign better, include an elite side of the story. Same ending and what not, just make a different perspective. Now, i'm not saying that elites are more important, i'm just saying that it would be fun to twist things up a bit. The reason why I don't say grunts, brutes, or jackals is because( and I think we all agree on this) elites are cooler and have a more interesting background story. I mean lets face it, before the halo wars, elites were civilized and not naked, but actually wore clothes.
Just a thought