Well, 3.1 will allegedly have some kind of NPC unit that can assist us in combat in the place of human party members. They haven't said much about it, so maybe they cut the idea, but we should hear more during this week's live letter.

I can't imagine them adding more NPC "party members" without clearing up the issue of whether or not the chocobo counts as a party member during dungeon queue, although I have a feeling it will fall on the side of NOT being able to queue.