I've been struck by the similarities to Into the Woods throughout. Not only in structure (that sense that things could end at the end of act/season 1, but it's so much more interesting that they don't), but also in how they both deal with story. Tutu is hitting a lot of the same buttons for me, and rocking my writerly world in a lot of the same ways.

Fakir and Rue both just become more and more and more interesting.

You're pretty much on about several things above, though not in the ways I, at least, expected early on.