Imperial Fists Basing

After playing around with the base and carving out some moon rocks for my scene, I think I have got it looking much better.

Here are the 2 options for his right hand, a bent elbow or a semi straight one with the same bolter. I Think I will go for the semi straight one, My reasoning is that it creates a triangular shape and the top of the triangle is his head which will be the focal point. Any thoughts on severed head position under the foot? 

I need to suck it up and fix the marine into position and sculpt his joints that I've cut to get the stance. Not forgetting his right foot, I might have to pop some extra milliput under and resculpt some moon rock for a steady footing.

Then I will hack up the genestealer (GS) in a dead pose. I am a little concerned about the size of the GS thigh it looks fine IRL but quite big in the shot, I'm thinking with the darker colours on the base to simulate sunrise it wont draw too much attention.