So, as I get to the end of Aether, there's a couple of things I know I'm going to alter when I go back and do the final draft:
1) The location of the Academy. Rather than be on another parallel Earth, it makes far more sense for it to be located in Faerieland, both in terms of my own world building and to make the story a little smoother. The fae having their own turf invaded and built upon also gives a bit more depth to their animosity with Illuminus.
2) Aurel. I kind of like him being a bit of a punch clock villain. It makes him relatable and I want to keep that. It makes sense though for him to be a little bit higher in the Illuminus hierarchy, rather than just in some throwaway job. This will help me to streamline things a bit as a role I need to give to another character can instead be given to him.
3) The infiltration and control of Illuminus on Earth will be a little more explicit.
Not retconning yet, and will write the story to the end with everything as it is - but these are the changes I will put in place later.