OP, having read the thread I'd ad Ashley Hobson Gwinett & Snellville; and Diaz at Harrison Tennis center to the earlier list. UTA produces a lot of talent as well, and i think it is all at Blackburn these days, but I'm not sure. All of these are north atlanta, if you are on the southside I really can't help.
While you will no doubt find fanatics for every one of these pros (my kids see one on that list), I beleive that any on the list will get you where you are going just fine. I'd look hard at the one located closest to you as commute has a lot to do with quality of life here. Personally, I've found that in the larger academies (Windward & lifetime for example) it's easy to get wrapped up in how many they have at the top. The real question is how do they handle the next tier?
I ran track in high school and college (D1) and speak from that background.