CLT wouldn't be too bad from ATL as it is an AA hub and you don't see a lot of delta personnel coming and going from there. PSA has a TYS base that I know is drivable from Atlanta because several pilots do just that.

Just because you live in the base of an airline does not mean you should necessarily just go there. I have nothing against ExpressJet and I have friends there, but even they would tell you to look at other regionals first if career progression is something you desire.