I'd suggest moving your last step to your first step, but other than that - PERFECT!
MootWorm already eluded to it, but you may be able to do without the second UTH or the overhead lamp depending on the temperature of the room that your tank is in. Once you have your primary UTH moved and the temperature steady on the warm side, measure the temp on both the floor on that side and the floor on the other side. If it's 76-80 on the cool side, then you don't have to spend the extra money on a second heating setup.
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Well over 100 degrees left unattended.