Atlanta and outlying: What are the best rental markets?

I am trying to narrow down the areas in which I’d like to buy rental property, but I certainly don’t know every possibility.

I do not want to be in the city.

I’ve thought about Macon, but that is about as far as I’d go.

What are some of the best rental markets (in terms of getting a good ROI without taking your life in your hands) within two hours of Atlanta?

Thank you.