I like your thinking - going to do some more research, but it's certainly a possibility.You asked for .02 so I might as well. I've been thinking about this myself. Since you have money to burn, here goes.
You're aware of the barrel/controller/bucket setup I have (Ebb & Grow by CAP). Imagine that setup with Flood Tables instead of buckets! The 55 gallon res would fill a 3x3 no problem.
Build a grid platform on the ground with 2x4s. Put the 3x3 tray on top and put the controller bucket on the ground next to it. Slightly raising the controller would allow you to control the height of the flood. You could easily run 3 or 4 controller buckets off one barrel at staggered times. You could flood a large area and only have to worry about dealing with the 55 gal barrel.
This would allow you to have the flood tables 4" off the ground. You would have the FULL height of the tent available. Plus, you would be able to walk around in there.
Right now I'm leaning towards just building shorter tables, and putting a "real" reservoir under them, something that runs more like 12" high - that would save me almost a foot, and then with the better reflectors, the 600s being able to be ~12" away, and then the extra 1' that I'll get by building it myself, I think I'll be straight.
Will have a large update tomorrow when this CO2 system is (hopefully) up and running - ducting and everything else is finished, just need an extension cord and to light the pilot and run some tests on it.
Four of the seedlings have broken the Rapid Rooter surface (2 Ice, 1 of each of the others), and the flowering plants are all looking as good as can be expected.