I agree the radius isn't appropriate to the house appearance. I would do all the changes to that window and be done. It also looks strange that it doesn't have the same exterior trim as the others. Wise to use true functioning hardware for the shutters. One other suggestion, the door could use an overhang.

Love your garage doors!

The trim is weird, though I did just have wider trim put on the rest of the windows and corner boards, but the original trim was not bad, just a little narrower than I wanted. The carriage doors unfortunately will be replaced soon with overhead doors as they let in too much cold air and there is finished living area above the garage. The new doors will be trimmed with the same arch to retain the look. We also have plans to add an overhang, as well as a third bay.

If you add that third bay raise the roof line and peak to match the section between the garage and main house. Old houses are all about symmetry.

You'll enjoy having an overhang to allow you to step out of the house and not be rained on, I added one to my house.

Hmm. Our architect deliberately made the third bay lower and stepped back (the center section is also stepped back) to make it subordinate to the rest of the house.

To me that lower roof looks odd, like someone drawn with one shoulder significantly lower than the other. The step back is fine, it's the odd roof alignment. I would redraw that portion and compare the two.

Here are mockups of both scenarios.

Here are mockups of both scenarios.