Definitely not bad
But not super-epic awesome, either.
Hair looks like you gave NPH a jew-fro or some such, far too poofy, if you ask me.
And I think his eyes would look better un-lidded, maybe more maniacal and less Evil-but-Tired.
Thirdly, we all know that Dr. Horrible always fists his hand as he pulls the neck of his glove down. ;3
Just an obsessed fan quirk. I've watched the Sing along blog far too many times... >>;
Anyway, just some CC to work on.