Alrighty, let's give this critique thing a try.

I agree with whoever said that emphasis is being pulled away from her face. This is happening I think for a few reasons. I want to pull the emphasis back to her face because she's got a really great expression that her whole body is leaning towards. (And yes, kudos for painting realistic boobs.)

First reason, because her hair is white, its outline fades into the white of the background. That by itself is a neat effect, but it may not be working here yet because the eye doesn't look at it long enough for the mind to fill in the rest of those shapes that we don't see. Now, the human eye tends to go to the area of greatest contrast first, and linger there longest. That means wherever there's a sizeable really dark shape next to a light shape, that's where we're going to be staring. The obvious and most interesting dark-against-light shapes here are the tie the bird's taking off, the shoes, and the belt under her bosom. That coupled with the red makes it difficult to get back to her face.

The second reason, is that the composition's natural lines never quite seem to intersect her head. There's a definite sense of movement in an X shape, implied lines that go from the tie-less bird's head down her arm to the bottom bird's leg, and another following her legs in a gentle arc up to the other birds' heads. These lines cross on her dress, and that's where I find my eye going back to every time. That in itself is a good thing, but I think you can work in one or two more implied lines to get the eye to travel further.

Hmm, now how to do all this... Perhaps a really big and dark earring will help bring the eye back up contrast-wise.

As for composition... I really think her head is too close to the top edge. It's causing her to not jive with the golden section. Currently the center bird is probably the one that is hitting a centerpoint of a golden section spiral, pulling emphasis away from her face. (I had a teacher who had a shortcut for figuring out where this is. You draw a diagonal from one corner to the next, take a third corner closest to where you want the emphasis to go, and draw a line from it that hits that other diagonal at a right-angle. That's roughly the center ofa golden section spiral, and is where you should place important things for the most emphasis as it's where the eye naturally wants to go.)

So, you can push her face closer to that point by just raising the top edge of the image so there's more negative space.

Now, I don't think the background needs more color, that would detract from her dress and the subtle blue beaks. It may need some more of that lovely gray in the shadow though. Hmm... Try... making most of the background that gray (may need to rework some of the shadows), and having the white light stab through in a great big diagonal that intersects with her head. That may work. Or maybe it won't, just play with it.

(Also, I'd personally like to see a little bit of white showing to the left of her legs, it may not work but you might be able to pull some really interesting shadow shapes out of that.)

Good lord, long critique is long. o_o; Forgive me if I told you anything you already knew. It's a lovely piece and a very interesting idea.

I agree with Sygnin, It's very hard to critique something like this. It's well done and elegant, but stylized enough that only you know its message enough to judge whether or not you've expressed what you wanted with it. Some information in your artist's comments might help. I suppose I could remark about the way her heels look like little more than sketch marks while the rest of the image has more strength and style with the detailing and color, but that in itself could be a style choice.

It's a nicely done piece, and I enjoy looking at it.