Thanks for all of the compliments everyone. Hopefully I can take a pic later this summer with it full of eggs.
We will be running a 1500 watt oil filled heater controlled by a Helix 1500 watt system with an auto-dialer (to call us if the temps get too high or low) and a fan in the back corner to keep the air moving and hence stabilizing temps from top to bottom.
Thanks for the compliment. We insulated the walls with standard R-13, then covered them with 1/2 inch plywood, and then covered the plywood with 1/2 foil coated styrofoam insulation. I still have to tape the seams, but that is still on the agenda. We turned the white side in, to help reflect more light, and thus allow better spread of light from one fixture.
I didn't want too many fixtures, as you can't leave the light on when you are not in it, or the ballast will overheat the room. So, the fewer ballasts I had in the room, the easier it would be to control temps