I'm not gonna lie, IMO none of them are very good. The background is bad and the lightings not very good. Try and tweak it a little and it could look better!
I lol'ed at the second one, his lower torso is missing. The rest are good too but are a little plain. Try adding some effects along with the backgrounds you used and i bet you could get much better results.
Well, IMO they either have to much light or are to simple and a poor remake of an original epic shot. I give it a 3/10, sorry mate try checking out screen shot guides to get some epic effects.