Well there’s many ways to do COOP. Yet I’ll just go by what’s been done in the past and some general ideas.
1-Everyone is Chief. Like in Halo 1 and Halo 2. Just an army of CHIEFS
2-One Chief and 3 Elites. Or 3 other non-spartans. Like in Halo 3
3-4 custom characters you create. Like in Halo Reach
4-Have a selection. Even if it doesn’t match the story. For example "A Spartan, a Brute, an Elite and a Spartan 3/4.
I for one would find #4 to be totally insane and awesome. I mean imagine having 4 Brutes going around on a team helping out Marines. Or a team of Spartans, Elites, Etc. And who cares if it wouldn’t make sence in the story. Have fun with it
P.S-Cutscenes are the only thing that may get in the way of this. Yet whatever.
But what do you want.
All Chief’s with different colours.
First guy is Chief, other three are their multiplayer Spartan-IVs, which don’t appear in cutscenes.
Needing to have 4 canonical players there at all times cuts down on story possibilities (I mean, think of the first mission - any attempt to explain how three other Spartans/friendly Elites magically appeared as Chief came out of cryo is going to be desperate to the max) - and if characters such as Thel are used for co-op, this means they can’t have their own plot threads, which sucks.
Custom spartans would make the most sense IMO. If there are spartan IVS on requim, why not play as them?
Perhaps
Custom CHIEF’s in COOP (like by color n some additions)
But more custom ability in Spartan OPS
I like idea 4, I mean who cares about canon when you’re doing co-op, and if you wanted it to be canon you’d just choose the characters that would make sense to be in that situation.