Since you cared enough to fix the rat's muzzle (thank you for doing that, I'm so tired of rats with dog faces), I figured you'd want the feet to be right, too: www.deviantart.com/art/Referen… I know it's hard to find references of them, and so many people give them paws that most people don't know they have feet, not paws.
Very nice design. I daresay it's almost cute, if not for the murderous gleam in his eye! ^^
I love the pose especially. I think you really captured the moment of him leaping towards an enemy with intent to strike him down.
Adding to what others have said previously about how "rat-like" the image is (and i appreciate this is rather late in coming), I think it's the unusual fur colour and pattern that might throw viewers off. I like it though, I was still able to look at this and immediately recognise that it was meant to be a rat person.