not too specific at all! I’ve just started reading TSOA myself actually.
Not a classic but definitely a retelling; Bitter Greens by Kate Forsyth is a retelling of Rapunzel set around the Italian Renaissance and it is one of the most beautiful things I have ever read in my life.
On the topic of retellings of fairytales specifically Juliet Marillier is quite good. Heart’s Blood is her Beauty & the Beast retelling, and the one that most people are familiar with is Wildwood Dancing which draws a lot from Romanian folklore.
Prince of Shadows by Rachel Caine is an interesting one, it’s a retelling of Romeo and Juliet but it’s not about Romeo and Juliet; the focus is entirely on Benvolio and so the story fleshes out the characters of Benvolio and Mercutio primarily, but also Rosaline. (another Romeo and Juliet retelling is of course Warm Bodies although many more liberties are taken)
I’ve heard some people say that Going Bovine by Libba Bray is a retelling of Don Quixote, although I’m not familiar with the original text so I can’t say for sure. It’s still an excellent book though, please read everything that Libba Bray has ever written.
I’m going to end with one of my favourites; the Mists of Avalon by Marion Zimmer Bradley. It’s the story of the rise and fall of Camelot told primarily by the perspective of Morgan le Fay (my queen) but also Igraine, the Lady of the Lake and Guinevere.
+ I’m desperately waiting on Tell the Wind & Fire by sarahreesbrennan which is a Tale of Two Cities retelling that is tragically not due to be released until 2016. Please also read everything that Sarah Rees Brennan has every written.