I love the mink and pewter loafers. The pewter ones have the benefit of being high vamped enough that you can easily wear socks with them when needed. I may be in the minority, but I also like the brown ones, and think the sliver of exposed skin is flattering, but the vamp is high enough that you could also get away with socks here. And I really like the silver, but not if they don't fit...
I'm in Atlanta, too. And because I walk to work, I wear a lot of flats. I also struggle in fall/winter because I much prefer either the leg lengthening of a heel or the slimming structure of showing off my calves and ankles. So I share your sartorial pain if not your physical foot pain.
Glad to see you're trying out the Pettys (if they don't work with your feet, a search for them on Amazon will show you other brands with basically the same style). I find that I can wear my Pettys with low invisible socks and exposed ankles in the same temp ranges (or cooler) as covered ankles and sockless feet. I've also been known to wear them with cute striped socks and rolled jeans or straight leg trousers, but not sure how that will go over in your field.
For January and February I move into skinnies with flat boots, leggings and tunics with flat boots, and skirts with tights and flat boots too keep warm and dry. It gets tedious, but then suddenly we get that 70F day in February and I get to put on some pointy toed flats joyously.