Hello and Welcome,
I also live in South GA, relatively near Savannah, but I have a different opinion of the climate. I'm an exceptionally warm natured person and I find Savannah's humidity to be horrible for my pain. I have to keep de-humidifiers on all the time in my house to combat mold and musty odors and the pain that increases with swelling. I do understand, however, how bad extremely cold weather can be, especially if you have hardware.
I'm inclined to recommend a slightly more Northern area, but not too far North to make sure you don't aggravate your eyes, as you mentioned.
I have visited the Northern part of GA several times and the mountains feel very different than the Southern part. I don't like to drive in moutains, but I do like the climate better in North GA. Depending on where you plan to live (city/country), the housing prices are still pretty low in alomost all parts of GA and the roads are pretty well maintained. I know SC has MUCH worse roads than GA in every place I have driven. For me, that matters in the pain area too because of the vibration and the "pot holes".
Perhaps you could check out areas above Macon, but not in or around Atlanta (where the housing prices/living expenses are still high). Milledgeville is kind of nice still if you like the large old homes (I love them). Augusta is not so nice in my opinion and has that problem with the humidity. It does have a nice teaching hospital though.
Joy.....please don't think I am trying to go against any suggestion you made (although it may look like it)......it's just that my pain and my body really react to humidity and heat so I have a different perspective on the cities you recommended. I'm hoping some others will chime in with their perspectives.
All my best!
Failed fusion L5-S1, Pituatary damage, HGH Def, Fibro, Bladder surgery failure, Nissen Failure, GERD, OCPD, GAD, MDD, CTS (Bilateral Surgery completed), CFS, TMJ, Migraines, Vit D, A, Magnesium deficiency, Pre-glaucomic (sp?), HBP, Idiopatic Reactive Hypoglycemia, Edema, too many Drug/Food allergies, sensitivites, and current meds to list.