I'm no expert, so I'll just give you my opinion!!
I prefer the colour version of this photo, but I don't think the vignetting works.
I've just been playing with a piece of paper in front of the photo and I would suggest cropping the photo from the bottom - by taking out the bottom window on tower 36. This keeps the shapes of the towers and their numbers but gives you a little less brown in the foreground which I think might be more pleasing.
Hope this helps.