i think for the first three, u should ude some greyscale and some color. maybe greyscale the stock, and colour around it or viceversa.
wow man you changed a lot since the last time i commented on ur works. You have a much different, and cooler, style now! In the first sig Nr.1 is the better. I loved what you did to her face, and the colours looked really nice. In the second one V.1 would look better is the border was at softlight I didnt like the sig so much, i mean it had a cool bg and all but i didnt like how the render looked in there, the quality was way lower and it made the whole sig look a bit worse imo, but great bg! Did yo made the Earth yourself? I liked both much better than your current
you should make the first 3 transparent (white parts) The halo ones... emmm I like it then I dont its weird I cant put a dime on whats missing (but I dont think its the fact that the bg and render doesnt belong together)
I really think that the halo sig (2nd from last) is better then all of them. Did you make the planet and the other stuff? If so, that is totally awesome! Great sig!