I would use regular sunlight or pull your radial lights back a bit and use soft shadows though this will add to the render times. I'm seeing some harsh shadows and also a bright spot on the front building. I like the first sky a little better. What you can do is add more of your photo image to the ambient channel of the background. Here is sort of a duplicate of your setup. The first image is 100% diffusion 0% ambience on the sky image.