It would be much more interesting if Delilah was a protagonist for the DLC for Dishonored 2 instead of boring Billie Lurk! There is so much backstory surrounding Delilah that could have been told from her perspective. Stories like: how she founded the coven in the 1835, how her and Breanna met, how Delilah and Luca met, story of Brigmore Witches from Delilah's perspective, or Delilah's time in Karnaca from her perspective, Dishonored 2's story from Delilah's perspective etc. As you can see, all these stories that I have presented would be way more interesting to explore than what we got with DOTO. Also her powers would be incredible to use.