This has been a great topic! For backround, I have lived in central KY for about 40 years off and on (Lexington, Georgetown and Frankfort), two years in East Tennessee (Greeneville), a couple months in Atlanta, 12 years in Charleston, West Virginia, two years in northern Indiana, and 3 years in southwest Ohio.
Of course, there is no Nirvana. I currently live 8 miles west of Frankfort, KY, in a rural area of curvy, two-lane roads. I love it. I bought 2 acres of land and built a small (1100 square foot) house about 8 years ago. I have woods to the back of the house, the road out front. I pay $541.00 per month on my mortgage, which is a lot to me, but probably not so much as in many places in the country. My electric bill is $130.00 per month, water is $30.00 (it would be $20-$25 if not for my hobby of gardening).
I like east Tennessee, and it would be hard for me to pin down a specific town or city. Chattanooga always seemed nice to me, and Johnson City. Knoxville, I just don't care for. Not sure why. Maybe it is because of the Orange Stain. (Being a huge college basketball and football fan, KY and TN are bitter rivals).
I also like western North Carolina.
For some idea of taxes, you might want to check the following:
https://smartasset.com/retirement/retirement-taxes
I love Frankfort, Ky because where I live it is 45 minutes to Louisville or Lexington, about 75 minutes to Cincinnati, OH, and maybe 3 hours to Indianapolis. Probably close to 4 hours to St. Louis.
I64, I65, I71 and I75 are all within 50 miles of my house. The Louisville and Cincinnatti airports are both within 90 minutes. The health care in Frankfort is OK, because specialists from Lexington and Louisville have a satellite office in Frankfort 1 or 2 days per week. Or, it is 45 minutes' drive to their main office.
Gasoline prices are about 30 cents per gallon less than Louisville, not sure why.
There are 4 areas of KY: Northern KY (greater Cincinnati): Yankee country, very northern feel; Eastern/Southern Kentucky (Appalachian Mountains, very similar to Eastern Tennesse), Central Kentucky (Lexington, Frankfort, Georgetown, etc). Rolling hills, beautiful horse farms, Blue-grass southern hospitality, Western Kentucky: Hot, flat, boring.
If I wanted to live closer to the mountains, I would look at Mt. Sterling, or Winchester, KY, both within about 40 minutes of Lexington. Take a trip to Natural Bridge State Resort Park, it is absolutely beautiful, and where we spent our honeymoon.
I am 62 years old, and just retired. Things that are important to me are weather, cost of living, health care, friendliness of people (we all wave at each other as we drive by out here), access to Doctors/Specialists, access to bigger cities, transportation (major highways), low crime, colleges nearby, etc. I like have 4 distinct seasons of weather, it is a little too hot/humid for me in the summer, but A/C handles that. Everyone out here has guns, as the police are 30 minutes away. Not that we have any reason to use them. But just in case, everyone has one. It is conservative in my area, the liberals live in Lexington or Louisville. If you ever want to check out central KY, just let me know. You are welcome to stay in our house, and I have lots of time to drive you around to meet the locals. Good luck with your research, and let me know if I can answer any questions.
Larry in Frankfort
https://smartasset.com/retirement/retirement-taxes