Keeping it cool enough in GA summers can be a struggle. Ventilation is key. I'd find a way to be able to roll up the sides as well so you can open them up when you kick on the ventilation. I got my hoop house kit from Nifty Hoops. Been pleased with it. It has automatic sides tied to the ventilation and 2 thermostats. When it gets over the temp I set, the ventilation kicks on and the sides roll up a couple degrees after that. I had to add fans and tie them into the thermostat with the vents as well. I'd get a couple long poles for the sides and seal the bottom side plastic around them so you can roll them up and secure with velcro straps. Just my 2 cents. Y'all did a bang up job building it. Looks great.
Also, leave enough room when putting in beds for a couple 55 gallon drums with a few holes in the side. During winter you can fill them up with compost for heat. If you have power you can also double up the top layer of plastic and seal around it then add a small air fan that will inflate the 2 layers. Will add insulation and prevent heat loss in winter while adding rigidity to structure (although you built solid so don't think rigidity will be an issue for you).
