Well I have had a re-look at the image taking note of all the comments and help and come up with the below.
I have cropped to remove some of the sky which has also helped to remove the distracting power line but I'm not happy loosing any more. The sky was boosted with my curves plugin using a gradient mask and the remainder of the image given a slight boost in contrast but not too much. A vignette was added but if I boosted this any more to be more noticeable at the bottom it looked too unnatural at the top.
Thanks for the advice and comments and hopefully you will consider this an improvement like I do.
Grahame