I love your use of color on this. It can be so frustrating, at least for me, to get a good skin-tone color. You did marvelous with this. I just wish that her clothing didn't look quite as flat as it does. that may just be personal preference though.
I figured that your main focus was on the girl herself which is why the background was blurred and it could account on why you didn't give much detail and shading to the clothes. For me I would have preferred a softer break or a better transition from it being rendered amazingly to the simplification of the shirt just because the whole piece seems to have a really soft tone. It almost doesn't look quite finished when you get to the bottom right. But the girl's face is such a strong focal point that it doesn't matter that much. Over all I love the piece.
I think you're making good sense..however the bottom right is ought to be lighter than the rest of the clothing because the light is coming directly from right angle, I'm sure that's why it's giving the impression of the clothing being quite plain.