I travel btw Carbondale IL to ATL GA frequently (live in Carrollton GA now). Pulling a load I would do I57, I24, to I65 and cut over to GA after getting into AL. B'ham AL to ATL GA on I20 west is a no go. Speed limit is mostly 55 with lots of traffic on I20. The only reason I suggest not going to I24 is to avoid Mont Eagle and Chatt TN. If the 40 minutes fighting the "hill" (and traffic) does not borther you then I would absolutlely go I57, I24, to GA 27 south. Briley parkway as you come into Nashville (Opry land, camping world, bass pro shop) takes you back to 24 on the eastside avoiding the city mixmaster (a must detour to take). Coming into Chatt on I24 27 north exits first and a few exits before 27. Great four lane divided hyway (27) with great views and parks Chickamunga (sp), Rome, etc. 27 will connect to I85 in Lagrange allowing you to feed over to I75 (either 285 east or GA 16 (two lane) or stay on 27 to see Calloway Gardens to Columbus GA (also scope Rosevelt state park and the little white house close to Calloway).
L'IL Foot" 2014 Sunseeker 2300
"Harry" the JK toad in the mirror