Welcome to Gaia! ::

Well, you have a good starting sketch. Mostly, you just need to refine and detail things a bit; the sun should look more, put together, I guess you could say? Instead of just a circle with lines. (though they are starting to have a ray-like appearance, you need to have a better transition between the rays and the sun, and add more rays). For the woman, add more detail to her hair (I'm not one to talk much about CGing, since I suck immensely at it, but with practice and some time, you should be able to make her hair look better). In terms of shadows, add some beneath her bangs, since hair casts shadows as well. See if you can add a bit more texture to the feathers, since, while they look fluffy, it's kind of hard to tell for sure what they are, and it just looks hurried and messy right now. The rest of the dress is beautiful, I love the concept, but work on fading it into the background a bit better instead of just abrupt lines. Work on her ears a bit; the one on the left has earrings in the wrong place (the bottom of the ear is approximately level with the mouth), and the ear on the right is too long, it should also only be about level with the mouth, instead of down to the chin.
Good luck! (P.S. I really like her eyes, mouth, and nose, very nice!)

Ah, gotchya, that makes a lot more sense now =)