Id say her face could use a little tiny poof, and maybe her stomach could be shifted a bit upwards, as if she was bending back....do I make sense? know sort of what I mean? oh well.
As for everything else, I dont have an eye for it, but Id also say its perfect.
1. perfect
2. perfect
3. perfect
4. perfect
er... if you really want me to pick at hairs to come out with something that you might try and improve, I don't think she's quite symmetrical, but that's OK, life isn't symmetrical and it's completly natural (as far as inflation goes), even charming for her to maybe bulge out a little unevenly :)
It's just overall really well done, I normally love your work but I especially love this style, maybe because it is more towards the 'inflated with something light' end of your own personal spectrum :)