great experiment....it has come very well against backlight, except the right breast overexposing in the sun..therefore, slight turn to her left cud have avoided this.
The only other thing (besides the overexposed chest) is her shoulders. I would have had her pull her shoulders back a little....as it is now, it looks a little bit like she's hunched over (to me it does at least).
No reflector for fill light. I am looking into getting a shade and reflector for these portraits I have been doing at the parks. When I get those Items I will through out a few more pictures for tips on them.