Thanks for the workshop! It's the first anyone's every done for me, so I was very excited :) I think you may be right about the river photo, but when this one is cropped the photo seems to lose focus, and I like the expanse of dark sky. Perhaps this shot is not as strong as the number of critiques suggests, because when you cut away what you consider "uninteresting", it becomes... uninteresting. One would have to then crop away the right hand side as well, leaving just the church. I'm not being sarcastic here; you're right that the tree isn't very interesting, but the the only thing this shot has going for it, other than the quality of the light, is the 1/2 and 1/2 balance between light and dark that works best in a square.
Thanks again for the critique, etc. Just because I don't completely agree in this instance doesn't mean I'm not grateful.