What? Do you think I'm nuts? ( Don't answer that, Alex. ) There's no possible way to make a judgement like that. There are just too many candidates.
Let me put it this way. Within five miles of where I'm typing, there are at least ten excellent parish churches. Each one a fine example of its style. There might be more. I'm not exactly sure where the boundary would be. Of those ten, at least six are first rate designs, worthy to stand with any of their kind in the United States. Three of those could even be called "world class".
That's just in one section of Toledo. Add the rest of the diocese, and I could easily multiply each of those figures by ten, at the very least. There are simply too many beautiful churches in the Toledo Diocese to choose one, especially since comparing first rate examples of different styles is really like comparing apples and oranges.
The award for the most beautiful parish church in the diocese, goes to the whole diocese for having an embarrassment of riches.