I like the POV in this one.
Matt very nice shot, in Sliver Efex use the control points to control the light. In the two upper corners add control point and darken some what to keep eyes from wanting to leave page, use a large circle of influence with the control point and also do not be afraid to add some structure to the sky to add drama. That dark cloud to the left is a great place to darken and add structure.
For me once back in Photoshop I would add a curves adjustment layer and move the black point to say 21 that will darken the image and give a good black, by having a good black, the whites will appear brighter, so the path will more easily lead the eyes upward to the person on top of the ridge. If the whites are too strong adjust them downs wards to say a output of 234. Only my thoughts on the image, we all do thing differently.
Cheers: Allan
Very nice image MattI agree with Allan about a more dramatic sky.
I like the revision MattIMO you need some noise reduction in the sky. I would brighten the top of the hill a bit if the image was mine.
PS. I think you have a dust spot in the sky.
Blue skies that look fine in the color version can look awful when converted to monochrome. Similarly, I've occasionally found that applying noise reduction and/or Gaussian blur to the sky in the color version produces better results than applying those adjustments to the monochrome version. Not always, but sometimes.
Nice capture of natural leading lines, nice conversion.
I like the second images, Matt...