A bit more attention to framing/ composition could help with this - a good subject but it looks like its about to fall over. Even if it is, it ends up disconcerting.
Nice shot. May have been better by adjusting the levels post production to brighten the sky and darken the windmill. A blue cloudy sky would make this stunning. The next sunny day with clouds go back and do it again.
Windmills are good subjects for motion blur... I think this particular photo would benefit from a tighter composition because the empty space is not adding anything to the image. = 5