Great work - I'm also working on my outdoor portraits, so I really appreciate this thread, as I need to improve.
Start looking around for articles on outdoor portrait shooting. Googling this brings up a lot.
A lot of these photos would have benefited a lot be doing them at near sun-up, or sun-down.
But you've already heard the harsh light comments. #4 and #5 would have probably been great if you had filled her face with a flash. #6 is wonderful.
My only suggestion is to plan the next shoot at sun-down, or a day that will be overcast and cloudy. But when you have to shoot in harsh outdoor light - fill flash, or diffuser. I've heard that a big white sheet will work wonders if you want a cheap solution. You'll have to find clever ways to clamp it...a tree, or something similar.
Or - simply find some shade. It looks like #3 was done in the shade, and it's very very nice.
I'll be doing a shoot at winery in a couple of weeks, and it has to be around 4-5 pm, so I'm also getting my harsh light strategies together! The first strategy is to get there early to scout for shady spots!