They are both nice, but I have to agree that the first is too dark and the second is too bright. Also there seems to be a little bit too much red in the contrast, if you toned that down a little bit and added some gradient lighting (lighter at the top, darker at the bottom while maintaining the focus of light on the lady) it'll come out better.
If you want some good professional advice, post this in the "Art Studio" forum at DAZ3D and let rg5a take a look at it. He was a professional lighting tech in a past life and will be able to give you some really good pointers.