With any of the models that I've worked with, one thing that I've noticed from all of them is that when they are looking at a photograph of themselves they look at it just like when they look at themselves in the mirror everyday. So while you're busy looking at a photograph from an overall value of how good the light is, is the pose something that works, the smile on the face and so on, she's busy looking at the few hairs in her eyebrows that are a little weird. At the same time when she's looking at photos of herself that she really likes, she's missing things like the toes being cut off in #1 and the heal cut off in #2.
These of course are things that you need to consider before even pushing the shutter button. Slowing down just a little and looking around the entire frame before hitting the shutter button is good practice to catch parts that are being cropped out. This will help in catching things that should be cropped out too, such as the various items that are stacked at the ends of the couch on #3.
I'd also like to suggest that your background can make or break a picture depending on how you use it. In #3 I have a hard time thinking of anytime paneling is going to be a great background when it's in focus and you can tell what it is
. Keep in mind that I'm talking about the background (the area behind the model), not a backdrop which can be inserted to cover up an undesired background. For example, the paneling could possibly work if you pulled the couch out from the wall ten or fifteen feet and used a decent zoom and shallow depth of field to blur out the background. By doing something like this you can make a more ordinary place take on an interesting look, and focus the viewers attention straight to the subject.
The hot spots on the wall are pretty noticeable to me as well. Careful positioning of the lights used compared to the position of the camera can eliminate most of this. If you dig around a little bit, Rolando has a post or two about "the angle of incidence is equal to the angle of reflectance" which can be helpful here.
Thanks for posting, and keep working on it. Practice is really the only way to get better. While I've figured out somethings, there's still plenty for me to learn for sure!