I certainty don't possess a lot of knowledge on anatomy, but I made a quick sketch that follows a similar pose to your character, I'm sure someone could provide a more accurate example though.
I think the thing that's throwing me off about your sprite is that he doesn't look like he's firmly planted on the ground. I think giving him a more pronounced curve on his back from the spine to push his torso back more would counteract him leaning forward so much. The sprite seems far to blocky and stiff, as oppose to the natural curve that humans seem to have.
And as IrresponsibleFreelancer mentioned above, I really don't think the diamonds are working; especially in a technical sense since they just don't read as diamonds. Putting anatomy to the side, having the diamonds there is really up to you since the design of this is pretty subjective. Overall, I still think this newer version is a improvement over the previous.