This is my take on the image, please feel invited to play around with the RAW and post your results:
This file is licensed Creative Commons, By-Attribution, Share-Alike.
ART-GIMP plugin White Balance Stretch3-Wavelet Sharpen
…looks like Batman is around the corner 
I think, the dark mood fits the clouds well.
Maybe you took it slightly too far, but definitely in an interesting direction!
Hello,
Very nice mood at the end of the day.
Here’s my colorful proposal, I’ve tried to accentuate the contrast between the warm and cold colors.
Greetings from Brussels,
Christian
Oh that looks exquisite, well done once again, Christian!
That’s quite close to what I had in mind early on, kind of an “end of the world, the alien spaceship is breaking through the clouds” type of mood 
DSC_2515.NEF.xmp (13.7 KB)
This is bad: Protected open space. Do not walk on the lawn, keep dogs on a leash, do not feed animals, bathing prohibited.
Thanks for the opportunity to play with this image. It is so open to interpretation. I experimented with base curve fusion, sigmoid and filmic. I settled on filmic. I also played with local contrast modules HDR preset for fun.
DSC_2515.NEF.xmp (24.1 KB)
A kind of experimental version… not much good but I wanted to try it! “It” being perspective ‘straightning’.
DSC_2515.NEF.xmp (9.1 KB)
I often think it would be a great feature if one could select between full and partial straightening, in order to let the results still look natural.
I agree. Full straightening usually looks overcorrected, it doesn’t fool the human eye. I believe the eye needs a bit of the original perspective retained for the image to still make intuitive sense. So the “correct amount of perspective correction” for any given image is always a compromise somewhere in between perfect full correction and the original perspective.
Edit: Just re-reading my comment, I’d like to clarify that I don’t mean to say that I put every image through perspective correction. The last sentence may come across as saying that I always straighten structures or such. To the contrary: on this image, like on many others, I’m torn on whether to even activate lens distortion and vignetting correction. Some images look far more powerful with the natural (i.e. actual, real) optical lens distortion in place, and I find that a heavy optical vignette can look fantastic in case the full uncropped image is used. I just don’t want to fall into automatic habits, especially with the basic steps of processing, because that would take away a lot of creative options.
I played with manual straightening with little success on the image. @123sg did a reasonable job.
You can also start with an automatic perspective correction and then ease back on just the vertical shift value to taste.
