Maybe you coud turn the sound quality up a notch. The tinny sound kinda raked my nerves. Also, if it's going to be pretty violent all the way through, that's not violent music. I'm not saying change the music. Just letting you know what I think.
Other than that, great art (even if it will be better later) and good action. It looks like it's going to be great. I don't usually like these previews, but yours actually got me wanting to see the real thing.