You shouldn't have any issues with Delta that some advance planning and airport familiarization can't handle. Where you fly through Atlanta on the way down, go to the Delta website and make sure you can visualize the airport layout in case your arrival and departures don't both go out of the same terminal. In a nutshell, the gates nearest where you check in from the street are the T gates. The remainder of the gates are alphabetic from there A then B then C then D then E (mostly international flights). Delta is in T, A, B, a few odd C gates and E. Most likely you'll come into A and leave through A, but if not, you'll need to transfer via train or moving walkway from terminal to terminal. It is pretty quick and I have made it in one terminal gate to another terminal gate in less than 20 minutes most of the time unless it was an international transfer. The center of each terminal has the escalators up and down to/from the trains with plenty of signs pointing you to them. The food court areas are there too. Coming back through Cincinatti, the only thing you'll have to check is whether either flight is on a commuter/regional jet. If that's the case you'll have to take a bus to terminal C to transfer. Best of luck in your travels.