I personally like it the way it is. I feel with the head in the upper right as suggested, the viewer may focus too much on what she's looking at (which is nothing very interesting - just some rocks). This is coming from a complete novice though.
Did you find the head this way, or did you set it up? What's the stuff on her face?
The flowing green hair disappearing into the soil and moss (?) gives her the appearance of some "Mother Earth" spirit thing. It recalls the animation in Fantasia 2000 for Stravinsky's Firebird.
My type of subject, and this one in particular is killer.
I'm not a fan of this oversaturated crazy-colour processing that you're using on your photos (at least the two I've had the chance to comment on today). That being said, I think that lowering the saturation a bit might make it more palatable to me.
Regarding the composition, I think it works very well as is. The rule of thirds is just a guide, much like the do-not-centre-things bit of wisdom. Composition is about balance (or imbalance, if you're trying to create tension). Here the head is tilted and the flow of the image is dictated by the direction in which the doll's eyes are looking, all of which is counterbalanced by the hair flowing to the top right. The result is great balance, at least in my opinion. I wouldn't change a thing.