Having lived in NOLA for a couple years (Coast Guard), I don't think you'd need gears at all...if I remember right the highest elevation besides the bridges was that one dirt mound in the zoo....
The only thing I'll say about riding in NOLA is don't think you're going to arrive dry and smelling sweet, man is it humid!
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If you have a problem, if no one else can help, and if you can find them, maybe you can hire the A-Team.