Brave New World was recced on Bright Shiny Objects, a multi-fandom rec site. The review summarizes the story far better than I can, slightly edited for length:
"Every now and then, you find a fic which reminds you of why you fell in love with a fandom in the first place. "Brave New World" is one of those. It is the tale of the professor of Muggle Studies, as she raises her troubled nephew and comes to terms with her job, her colleagues, and the difficulties inherent in being a Muggle teacher at a magical school.... it is remarkably compelling, and well worth the mental time and energy it will consume. Miranda may look like a Mary Sue, but she is a million times more interesting than the beautiful exchange students and mysterious Defence Against the Dark Arts teachers that populate fanon. Her integration into the universe is helped by the fact that every other character is perfectly written, especially Snape, who is as snarky and cruel as his canon incarnation, and as intriguing and attractive as the fanon version." (Used with permission. Thanks, Liz and Teanna!)
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Contacting the author: theatresm is currently without regular access to email. News of any updates -- as well as access to Chaos is Come Again, a new Hermione/Snape fic -- can be found at theatresm's livejournal. (You will need a livejournal account [free] if you wish to comment.)
BNW is COMPLETE and was published before the release of Harry Potter and the Order of the Phoenix. It is therefore solidly Alt-Universe.