These are nice. I like the rim lighting you're getting on some of them.
Now, that said, they're a bit too high contrast for my tastes. I'd prefer a smidge (well, a lot) more fill coming from camera right. Also, if I'm picking nits, either do something in PP to fix the reflections in the glasses, or get the model to take the glasses off completely. The reflections are distracting me.
But you've started to get the hang of this type of dramatic lighting. I'd love to see some more traditionally lighted portraits (i.e. a key, fill, and background light, with perhaps some hair light thrown in). Since you have only two flashes to work with, I'd suggest a key at 45 degrees, a reflector providing fill, and using the second flash as a background light (not as a rim/hair light, as you've done here.
Also, experiment with different styles of lighting; these are all short. Try broad lighting, Rembrandt lighting, butterfly, etc.
Good job!
How are you controlling these flashes? Manual or ETTL?