I think if you had the sash thing blowing around in the wind behind her, it would look pretty neat, assuming the sash had some width variance on it. Think Makoto from Street Fighter III in the other post -- notice how her yellow bandanna thingy thins out in the silhouette and changes a lot over time with more of a varied wind "sound" thing like PPD mentioned on the other page. The rhythm isn't clear enough in these, and I think the sash, if done correctly, could help to unify that. Do keep in mind that even if the wind is blowing from the right-to-left all the time, unless she has a FAN on her blowing at a steady constant speed in a laboratory environment, the sash, like in all the shampoo commercials' supermodels' hair, would be flapping and flopping around in a somewhat unpredictable way. After all, wind never blows in a steady stream -- it's always gusts.
I think the thing you /really/ should remember is that Animation is all about CHANGE and PUSHING your animations past where you're actually comfortable pushing them in order to add interest. This applies to static images as well, but doubly so in animation!
The wrong KIND of change, of course, in the wrong context, can kill your image -- though, don't ever be afraid to PUSH it regardless, because this can save your ass a LOT more times than not.
A good example of this:
The sash was a great idea, but you just didn't push it far enough. Had you exaggerated it as far as you could go, you likely would have realized that the wind blowing on it was too soft and too constant and thus appeared unnatural. In PUSHING your animation, you would have realized the physical limits of what was possible with the sash and could have executed it stylishly the first time.
With a few mods to the silhouette and potentially adding a bit more to its 3d-ness to break it up (I assumed it was a snake or smth around her waist at first), you could do well with the belt/sash idea as long as you PUSH the animation hard, and then just soften it as you need to from there (but the extremes will still exist behind the animation, and that's a /good/ thing -- always).
Other than that, when she bends a bit to take her hair band off, you should show more change to her knees/butt by bending her silhouette more to give it more life (adding that CHANGE that I had mentioned before). I apologize for emphasizing these words, but I want you to be more aware of them. You've got a LOT of potential, and you only need to be more aware of these two things to get closer to where you want to be. If you admire PPD's work in animation, you should notice that he uses BOTH change and pushing his work to extremes to create the interesting animations (as well as static art too!) he creates! Seek to change and push your art and animation (static art too!) as far as it will go (try to break it!) As long as you do this first, you will always create more natural and more interesting things than you would ever do otherwise with external inspirations and references!