Eh. The Powerfist idea would look better on Crimson Fists, I thinks. The huge red fist/equally huge blue body would look nice. The LC on the IF commander is a nice detraction from the standard. Good work!
By the way...is that icon on his banner Forge World, or sculpted?
i kinda like the fist emblem popping off its like proper embroadery which is slightly raised, but i agree with the lighting claws comments they make me think of space wolves or even blood angels but it all comes down to how you paint him. you can draw the emphaise to the fists and not the claws.. nice work