My experiences with Legacy are about the same as Cuzfloyd, bought 10 Legacy plants a 4 years ago and even with the proper care they were extremely slow to grow and produce. They all got yanked out.
Loud, I recommend you stick with rabbiteye varieties, I also live in the ATL area and our area is about perfect for growing rabbiteyes. My favorites are Titan, Premier, and Brightwell. These are superior to older varieties like Climax and Powerblue.
The PH of my clay is naturally about 5.0 so you probably do not need to lower the PH much. The general recommend for our area is getting a bag of Sphagnumpeat peat moss that you can get at Lowe’s, etc. and mixing it with the clay and plant in soil mounded up at least 3-6 inches then mulch with pine bark.
Blueberries are very easy to grow in our area, I have around 30 plants and looking for room to add more.