The b&w conversion works great, once you get a nice tight crop that puts her on or near the third vertical. When working with thirds, I'm not a stickler for both vertical and horizontal thirds at the same time, and in in the crop suggested, you end up with too much (for me) white space above her. I'd hit the aspect ratio you need (3:2 or 16:9 for web, or 8x10 for printing) and just get her near the third but the ultimate measure of success is a balanced composition, not necessarily hitting dead on the thirds.
Also, I think the reason that the b&w conversion works so well is that the light is very flat, the background is very flat, and the background is already grey. Not a bad thing (many people would kill to get the soft light figured out), but if you want the color image to work, you have to bring more color into it than just her shirt.
In the last one, while I'm a fan of head wraps and such, but in this one it looks like she's smothered by it. Something heavy like that, I'd have her holding, twisting, winding, unwrapping, doing something with it, so I could get it to frame her, but I could also get it to lift off her a little so she can breath, and also maybe get her hands in the picture, and/or get her expression to be more dynamic.