Zebesian Lobster

[Chris2Balls [:B]]

shading it means you'll be looking at your sprite more carefully, and you'll make tweaks to both shape and volume.
for now, the left sprite is clearly off-balance.

i've put your sprite in comparison with other space pirate sprites:

you'll notice i've made lines for the feet, head, and curve of back to give an idea of how the weight is distributed.