Personally I think the bloodied version works better. You may not want to go with blood, but if you're going to take the effort to make different animations for different health states, it would probably be worth your while to differentiate noticeably between them (the previous low-health animation, to be honest, barely looked any different from the healthy one; in fact, if I hadn't read your post, I would have thought you accidentally posted the same images twice).
Some ideas to try in lieu of (or even to complement) the bloodied version:
tattered clothes, tired eyes, mussed up hair, a more horizontal, or even downward-pointing, orientation for the sword (to show he's tired).