Nice image Karl. For what is essentially a 50/50 horizon, the comp still feels dynamic due to the undulating nature of the ridgelines, so overall the composition feels well balanced. I like the texture and the colors in the landscape (and that the two mountains look so different in this regard). I enjoy seeing dynamic weather like this, it is working very well for you here.
To me the sky looks like it has a slight green color cast, although that is not the case in the landscape (it is Ireland after all). I might also clone away the telephone poles near the bottom too. Here is a rework with reduced green in the sky (land untouched) and the cloning.
I don’t see it as a color image at all so I went for a B&W treatment. You have quite a few dust bunnies that don’t show in color as much as they do in B&W. I also cloned out a few of the telephone poles.
I didnt think of a black n white option - one thing though, points to a good process of cleaning dust spots
Besides that, I might trying on making the sky more dramatic
I was going to say exactly what @Ed_McGuirk mentioned about the green cast! This is a lovely location though and some really cool light on the foreground hills. The black and white from @Chris_Calohan is a great idea as well, I agree with you though that it could be a bit more dramatic with some more work! I think by doing so you could draw added attention to the slope on the right and the texture in the hills on the left.
Now I feel that the sky ( besides the color cast and dust spots ) may need a lttle more work - perhaps to infuse some contrast and depth, yet keeping the fog, fog