There's already quite a host of music places, and if it got a bar it would be a shame that there would be yet another place I would not go because of smoking....
How about....
The East Atlanta Performing Arts Center!
I have no idea if the stage area could be made larger to accomodate sets, but it's an idea... And it's a space that the whole community would enjoy. I don't have kids, so I'm out of the loop, but what kind of arts activities are there for the wee ones in or near the EAV? Particularly kids whose home environments may not encourage artistic exploration.