Some thoughts for Chris's piece  --

Generally a physically powerful human is drawn with a smaller than normal head. This guy's is big enough that he doesn't look strong, and his towering over the mind flayers makes them look small. 

The axe head parallel to the image plane flattens it. The purple blood on the blade isn't relating to the torn cloak enough for it to read as the mind flayer has already been hit (and the injured mind flayer isn't acting any more injured than the other one).

I'm thinking tuck his chin, and lift his right elbow to put more power into the swing. Move his legs (thus, feet) out from under him to put him in motion, and if his left shoulder and right hip are both moving forward you'll have a twist to his core, for another bit of motion.

Rim lighting on the undersides of the Illithids (tentacles and hands) flatten them, and undermine the light source, so I'd get rid of them. Sometimes darkening the piece is a good way to emphasize lighting.