Well I think this looks great, background or not, I think a background would ruin it cause right now its obvious the attention is supposed to be on this pretty mofo. To me a background, would like, take all the attention off the detail in him... or maybe that's just me.

That looks so cool! I love that pose...you don't know how many times I've attempted the same pose! You are awesome with the anatomy^^ I love all your ideas; keep up the outstanding work!