To start, I'll address what I suspect to be part of the issue, and that is the lack of cooling air flow into the center of the front rotors. In the quest for increased gas mileage, Toyota has not only tucked the wheels decently up into the wells, but also added 4 small lip fairings just ahead of the front tires and supension. They direct air in a way that will help it flow around the suspension and tires w/o getting caught up and increasing drag. Toyota has to meet CAFE standards, and this is one way to do that... it would not be there if it didn't work. Unfortunately, this does not guide any of the air into the small slot vents in the backing plates that feed air into the rotor centers. The vanes in the rotors are on their own to pump the vital cooling air. So the first part of this project will be to add cooling ducts or scoops of some sort to catch and force air to the rotors. I'll come up with some designs and post them up.
Please feel free to add to this in any constructive way.