I don´t expect a campaign mode even if it would be awesome. I guess it need a ton of work to get it somehow working. They can invest their time in more important things. The core game should be playable without any bugs and should be feature complete before we should even think about stuff like this.
And we are faaaaar away from that.
The only "easy" thing I can think of are coop battles. Like the second player can´t do anything on the campain map but is able to join your battles to play one of your soldiers. But that would be boring for the second player I guess.