Yeah I agree with version 4 being the best for sure. I would like to see you try moving the sun or whatever it is you have as a light source there, and placing it in the bottom right hand corner just above her knee to give yourself some more depth through-out the work and to match the colour tones you have used. As of right now I can see that the top left is almost white, and with the trajectory of the light facing towards her face, chest, and arms, you can almost determine where the light source should come from by looking at the spots with the most light on the render. I think it could change the overall look of the sig for the better, but hey just my opinion! Still love the sig, looks great, just needs some work - Arc.