A few thoughts:
1. I like the lighting on her face, but her dark eyes and the lack of a catchlight leave them rather featureless. Additionally there's virtually no detail in her black top. I think a single large SB a couple of stops below key slightly camera right might have helped a lot.
2. Nice, notice how much more life that single catchlight adds? When you have the models turn their head, try and avoid having them turn so much that it forces their eye all the way to one side; ideally a little bit of sclera should be visible on each side of the iris.
3. I wish you'd brought the key just a bit farther right; her left (image right) brow and eyelid are mostly lost in shadow.
4. Nice; you could have pulled the lights a little closer toward the lens axis, but as-is, it's pretty good. Not overly fussed about his expression however.
5. Either drop the key or use a reflector to bring a little light into the eye sockets; nasty racoon eyes here, but good light everywhere else.
6. Nice! I really like this one.
Just my $00.02 worth - your mileage may vary.
~John