I think one of the next big steps, over the next couple of years, should be to increase the amount the variety in facial and body animation that the in-game models are currently capable of.
While the faces are better off now that their mouths can form words and are able to produce some expressions there is so much more they could do. Bring more life to their expressions, make them feel less like robots and/or puppets.
They can form words now but they but we are not quite there yet to what this video was showing. Notice the subtle facial movements as they talk. How they have body language.
https://www.youtube.com/watch?v=44gn3RlYKyA