You are putting too much effort into your shading.  Since the scale is so small, single pixels don't amount to much, so trying to do nuanced shading just amounts to a bunch of static.

You have to simplify the light and get it down to it's most basic aspects.  Broad shapes of light and shadow, and well placed core shadows and highlights.

You don't have a lot of space to work with, so you want to have the readability of the image to be really high.  Be spare with your colors, and try to use as few as possible.  It's easier to add that reduce.

What if for an idle animation he was sort of shifting side to side with his knees bent, keeping his hands moving, alert and waiting for a fight.
Or he could do some leg stretches, that might be neat too.