I generally like the lighting in the first shot. I find it to be appropriately lit with low light, not underexposed (I see good detail in her back, hair, and the lit side of her dress). I think you did a good job balancing the light levels between the model and the background. My gripe is that her lower leg is not lit as much, I think you could have adjusted your lighting to bring this closer to the level on her back which would give her more cohesiveness.
I find the second one to be nicely lit, you've successfully illuminated both the parts of her near the camera and her far-reaching leg. It seems to be exposed well, nothing blown and the shadows aren't too deep. However I feel the light level is too bright for the scene, it clashes with the lights in the background. This shot on seamless would really work for me, but with the brightly lit railing and the dimly lit background it feels off.
(And since it has come up, let me say that I like the posing. It tells a story about her physical prowess, and there's nothing wrong with poses that are unconventional and make the viewer stop and look twice - and maybe even feel a little uncomfortable.)