I too am disappointed in that Lenox/Phipps intersection, it's very pedestrian unfriendly, they should just open up those two malls and combine them. expand each one to the corners and then just build a tunnel or habitrail overhead to connect.
Or you could even leave as is, but turn the thing into a great tourist attraction. Imagine a huge skybucket ride with peach shaped cars carrying shoppers way up high for the view as they go back and forth between malls.
For the adventurous you could have a tower on each mall, with a glass elevator that takes you to the top. They strap you in and you then zipline your way over the parking lots and busy streets to the other mall.
Or for the real dare devils, the Buckhead Trebuchet, that would sling people in catapults flying in the air from mall to mall. Imagine driving down Peachtree and seeing the old blue haired buckhead ladies flying overhead.