First, you need to bring down the highlights and bring up the shadows. This brings out the details in the bright sky and low lit building. You need to remove the bird flying to the upper right of the cross (in the red circle). The main problem however, is the overexposed area shown in the red circle above. There are no details here. Next time, expose correctly for the sky and then recover the shadows.
My conclusion after looking at the picture:
Looking at the picture at 100% and 200% will show the troubles.
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