Does anyone else think Hordes of the Underdark should have allowed you to betray the Seer and then have the Valsharess instead of Nathyrra or Valen as a companion for Chapter 3? She could’ve been grudging or maintained her egomaniacal nature, especially at the start of the Chapter. Maybe she would gradually warm to the PC (though a romance option may be taking it too far), maybe not, but she definitely wouldn’t side with Mephistopholes at the end.
Every time I play through the campaign, I feel that the designers missed an opportunity. I suppose one day when I have tons of spare time, I could try to add that.