The delicate beginning that promises so much and blooms into delivery upon delivery of those promises -- when we see mention of Mary and Reg and then discover that you have taken everything from canon and given it depth. Gilbert and Finn! The echo of Tom Riddle hurting animals in the orphanage with the realization of how brilliant Albus had reached his conclusions; the hint that perhaps Aberforth had been framed for those inappropriate goat charms. The pitch-perfect depiction of suffragists and the reform outfit and the Hogwarts girls leaving after fifth year (yes, the age when Harry's year receives those helpful career pamphlets) and the dreams of women's education; I went to just such a school, and you nailed it.
The hippie girl with the husband and two beaus -- Lily? Who were the two?
But the moment of pure song came for me with your revelation of the cost of what Griselda did. Of everything that was lost, including their love affair, the greatest violation was of Bathilda's work as a historian. Wow. Wow. Wow. Wow. Wow.
Whatever we've done to deserve you, Mystery Author, I'm grateful. You are a gift.