So there it is - my take on the library.
I better not even say I'm finally back because I don't trust myself...
Hm. Now that I think about it, I have an interesting question:
The armillary sphere you've drawn. I wonder: Does Equestria follow a Ptolemaic or Copernican model of the universe? Ptolemaic would imply the planet of Equus is at the center of the system, while Copernican would imply the Sun at the center.
The outfit is brilliant. The accent of her gold and crimson slippers helps the navy and deeper pink of the outfit stand out, and the colors also work well against the rest of your backdrop.