Ditto, the lighting as per Lyrra. Ditto, the left arm as per maclean. Try the "squint" test or blur the picture, something to reduce the detail down to the basic levels of value and see where your eye goes. The left fist values are so close to the arm as the arm is close in value to the wall behind that it all melts together. There's no rule that every picture should have eye popping contrast. It's all about Your choice and there's a lot of looks to choose from. I'm working on a very similar composition at this very moment, although our content is Very different. So your question has been very "in my face" for the past few days. Right or wrong, I've chosen to focus most of my lighting to the front on the attacker and to get the camera as low as possible. But that's just how I'm solving my problem. Oh, and I don't believe that the set is too small but it is competing with your central characters for focus. I'll post my endevour soon. Good luck with yours.