Upon further inspection of all of my windows, they're all straight flat glass. I can't seem to find any sort of curve in either the glass or the frames. The straight frames do look a little out of place compared to the curved walls surrounding them, however it's something I am okay with.
I'd really like to stay away from storm windows as opening and closing the windows for ventilation is a huge plus. The Seitz windows that I've seen also come with built in screens and often blinds as well, so that takes care of needing to come up with some flavor of window treatments.
I do agree that i could just get some new window hardware (cranks, latches, and screens) but the existing cranks are really rickety-feeling, and I have a feeling that even with new ones, the whole assembly would still feel sub-par.