My little contribution to this whole endeavor so far has mainly been using some mocap to create a set of somewhat convincing "idle animations" that will blend together randomly. If I understand correctly, your Alive plugin could also be added, or the ticklish plugin, or something to layer on top of the motion capture to add a little bit of visual reaction. (You know, plus the standard Glance or Life for those without Alive) Maybe my bar rather low for this, but even just these few things combined with a lip-syncing chatbot provides an incredible level of immersion for me even though it's still in an illusory state.
