Honestly I feel the background is sort of... off. Not necessarily clashing, just off. I think the cause of this is that each of the women seem to have their own different perspective. The middle one is viewed as if seen from head-on, while the one on the right seems to lie on a plane that faces us a good deal more. The left-most woman's perspective seems to be somewhere between the two. And judging by the progress you've made since you started this piece, fixing this is probably going to be tough.