I generally love concepts and sketches, since you can see a sort of evolution of the thing.
Also, some of you works are very interesting, and since i'm writing a pen and paper RPG based on mlp, i would ask you if you mind if i got some inspiration of your design, especially for those valkyries, that are quite interesting as concept. Obviously i will credit you as origial creator of the concept from where i got inspiration.
I do actually. [link] These here are my Valkyrie royals, Brynie (who's not really a princess but close enough to it), Queen Freya and Princess Raven. [link] And this is a little bit of info on the Valkyria. Have fun!
Now I'm curious what Luna would think of that old book. I can't remember it having much of a story to it other than saying goodnight to everything, but with such a strong focus on her moon, I doubt Luna would think poorly of it.