I agree on adding animations such as those you mentioned, and cycling through them randomly. But if i remove the breathing, leaving just sporadic animations, the sprite tends to look static and lifeless. I think some sort of continuous movement is needed, even if barely noticeable (at the size this shows up, even just one pixel moving is quite easy to see), and breathing seems to be the most probable and significant movement at that size. I did try to keep this to indicate the lowest possible pixel movement (to my abilities), so it would most realistic, while keeping in mind the size.
I hope it doesn't sound like i'm rebating critics, i'm just trying to find a balance between them and my views, not losing sight of the original vision while at the same time finding out it's weaknesses...
By the way, love your stuff
and hope to hear your comments anytime you please.