Wow, I love the texture, and the colouring you did here. The shadows and highlights are incredible, making this piece have kind of an old style portrait sort of feel. The hair is amazing, still having to work on that for myself, but you did an outstanding job on it my friend. Keep up the awesome work here!!
The textures are amazing. This hair feels like actual hair all the way into the shadow behind her head, incredibly well-rendered. These feathers feel like feathers on very old pictures by them revered masters of art, the same sort of easily felt fluffiness. The texture and feel of the mantle is that of actual metal properly embossed and polished and such, and that gem also feels like an actual gem. The lighting work here helps it all come together, and is remarkably great at showing what her wings and cheek and neck are shaped like.
It may be a little experiment, but if you do something like this in full, you'll easily be one of the makers of the most highly-detailed pony art ever.