During the processing of this image, I soon discovered its shortcomings. The biggest problem - the horizon was tilted just a bit. No problem, we can fix that - need to keep all those horizontal and vertical lines nice in straight with an image of this kind.
Well, straightening the lines means cropping afterwards to get the picture square again. Yikes - upon doing that, I lost the top of the roof! And the lens distortion for this wide angle shot was even more pronounced now that I had closed in on the building.
Since I only took the one shot, this was the best I could do for this image. I have been concentrating lately on exposure compensation and bracketing, but upon viewing an image like this, it reminds me to also consider the composition, and take an extra one or two shots for it as well.