I say: "anything that slows down release and development of the mod is disposable." Personally I will just be happy to play Multiplayer when the mod is released. If they ever manage to make a single player campaign, for me it will be a "hey, cool" moment but I would still devote alot more time to multiplayer and league play. (once some leagues are set up that is.)
AI would be great for a couple for thing, (like machinima and costum campaigns.) But i would like to be playing along time before they would finish the AI. (Except for base turrets, they are to handy not to have.)