Sigh, you've just gone too far :-( The clouds and the foreground simply don't matcxh, and everything's glossed over too smooth :-( Helluva scene, though.
What's the point with the clouds? They were quite beautiful enough, I suspect, and needed no help in Photoshop. The desaturation further takes away from it.
I get to the critique on processing later but first I want to take about the lovely scenery. You have strong compositional elements with the interesting clouds and the fabulous open landscape with windmill. I know what you wanted to highlight given the title, but I think compositionally the shot would be even more visually appealing if you cropped out the top 1/3 and turned this into a 'wide screen' panorama. I would still have some of the fantastic clouds but not too much. Doing so would further play on the strength of the wide open feel and show off more of the windmill. This is a great shot but the over processing just ruins it. The clouds look far, far too heavy with the deep dark shading/outline that does not match the landscape below. It is so processed that it takes on the appearance of it being pasted in. Hmmm, I wonder now if you made the skyscape B&W but kept the windmill and ground in color which would explain why the deep dark light on the sky doesn't match that of the well light and cheery colors of the landscape. You have a fabulous photo here it just needs to be re-worked so the processing lets it truly shine.
Now I a big fan of Dodge/Burn. you seem to have nailed it with the wind mill, but as for the sky.....way to much. Also watch the fine detail on the layers. Notice the tops of your tree. (You may know this trick, but we are here to help so...) in Photoshop select what you want the best you can, then hit shift-Q, this turn the area a pink color. Use the paint bush to get the fine paint the fine detail......play with this. GOOD LUCK
You took a big chance. Vermeer would cringe. I like it though. It's more like a set for an opera thinking of being brushed and evened out with lighting. But I would not have separated so harshly the clouds in B&W anyway.
I think the photo had some potential but the editing leaves me wondering if the windmill or the sky was supposed to be the main subject, when I first looked at this shot I did not even notice the windmill which is bad decause I really don't care for the sky. The selective desat seems to divide the shot into two opposing images that do IMO nothing to enhance each. I would love to see the original sky, looks like some pretty awesome clouds.