I think the chances of a great deal of the cut content ever returning is slim to none. Epilogues are obviously coming, probably some stuff like Minthara's romance or Karlach's ending that everyone's talking about, but a lot of the sweeping changes are pretty much baked into the plot at this point. I don't see consequences for using tadpoles/removing them or the cut Upper City making a comeback and its associated endgame content, etc.
