Alpharetta is lovely but depending on the time of day the traffic on 400 to get to the airport can be rough. Great area though as are the surrounding cities of Roswell and John's Creek. Dunwoody/Sandy Springs and Brookhaven are also great neighborhoods with a shorter distance to drive but a bit more expensive. I personally love the west side of town and recommend looking into it as well. Vinings/Smyrna is very conveniently located to ATL and easy to get into town while still being quiet and safe neighborhoods. Marietta as well a little bit further up. Or West Midtown (i guess it's called Westside these days) if you want a more urban feel. If you're into investing and want to gamble on property values in up and coming areas that aren't quite as nice yet, the Chamblee/Doraville area has lots of opportunities and two routes to drive to ATL giving you some options with traffic. A few of the downtown neighborhoods are getting redeveloped quickly too but i personally wouldn't be willing to put up with it during the process.

Then there's always PTC and Newnan if you're into that but I like being closer to town.