Security ... think about it!
First, if it is possible, begin packing at least two to three days in advance. At least try to have all important items packed a day in advance. Nothing is more stressful than packing the day you are leaving for an exotic vacation and you leave your digital camera. Second, since Cobb County is approximately a 30-40 minute drive, depending on which area of Cobb you are coming from; adding another 15-20 minutes onto your commute will assure that you arrive at the airport with plenty of time to check-in, maneuver through security, and catch the monorail to your perspective gate. In addition to, avoiding any potential traffic delays, that could hinder your arrival time to the airport. Finally, wear comfortable clothes in case you are patted-down, hopefully you won't feel that the pat-down is too intrusive, if you are wearing clothing that you can feel relaxed in.