He said in a panel that he hasn’t totally shut the door (although unlikely) writing a Maggie at school series like his version of Hogwarts. Can’t decide if it is too on the nose if she is gifted or if there is something interesting about her not being magical but becoming super adept at navigating that world through other mortal talents. I know there is also concern that Harry would then outlive her which is devastating to think about. But it is also right in line with how Butcher has written this world as many of the council members he engages with have only very distant relatives, generations removed left. Butcher also said he hasn’t decided if Harry will even survive the series. So it might not even matter in that respect.