The fact of the matter is that not everyone has Xbox Live. Even if you do have it, sometimes you want to brush up before taking it to some flesh-and-blood chumps. How about some programmable bots like the ones in "Perfect Dark" for N64? In a pre-game menu, you would be able to program skill and attributes to the bots as well as assign skins like, Grunt, Marine, Brute and so on.
A cool spin on co-op. One player is the Chief, while someone goes through campaign jumping from Elite to Elite (also cribbed from "Perfect Dark"). Put this on Xbox Live and you could have several people as Elites battling one unlucky Chief.
If only one wish were to be fulfilled, let's hope it's this one: Co-op on Xbox Live. You and your buddy duking it out side by side, each on your own box. You could work out your own geeky field jargon. How about teams of four? Bungie could weave this into the story by having the SPARTAN program resurrected. Or the game could just let you play as Marines or ODSTs. Let's blow it out -- how about a massive online co-op campaign mode with 16 person teams and Marines? We're talking big, no huge "Lord of the Rings"-scale battles, in big open fields. Man oh man, that would be fun!
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