I like the idea of another Halo after the reclaimer trilogy, but I don't see how 343 would be able to do another campaign. It couldn't be about chief again, and as Halo : Reach proved, nobody wants to play as anyone but him. Also, I think after the Reclaimer trilogy ends, there will be no more big conflicts in the Halo universe that need to be resolved, therefore no more Halo Halo needs to stop at six so it doesn't end up like COD.