This is a gorgeously magical book, with a fierce heroine whose voice I loved. Isabel Sterling is determined to save the House she loves - and the boy she loves, too - and I loved her strength and determination as well as the magical system in which the Great Houses of England are given literal magical powers and individual personalities (but also a subjection to the whims of the king that can BURN). The symbolism is fantastic, and the relationship between Isabel (as would-be Caretaker) and her House, Burleigh, is SO powerful.
The only thing that took away any of my personal enjoyment as I read was that the details of the alternate history never quite lined up for me, speaking as a total history geek/long-time alt-history reader. Personally, I wished that more of that larger history had been given so that I could understand which century this was meant to take place in (alt-17th-century? alt-19th-century? I kept shifting between which era I guessed) and how history as a whole had changed because of this HUGE change in the structure of British society which had also apparently led to a change in the ruling family of England and their European alliances many centuries ago (while still leaving every British place name exactly the same and referring to one of the exact same novels of social satire having been written by the exact same author, which baffled me). However, this is a YA novel, not an adult one, and I cannot imagine any teen readers (or, for that matter, any adult readers who aren't history geeks like me!) being bothered by those very small and niggling questions in the historical worldbuilding.
Far more importantly: I truly loved all of the characters, and Isabel's relationships - with her foster family, with her (wonderful) love interest, with her neighbors, and most of all, with her House, Burleigh, are SO well done, so intense and powerful, that they absolutely carry the book. I cheered for Isabel (and Wyn, her love interest) all the way, and I really enjoyed their story.