Corey,
The R3 has to be better than a HD. Two friends swapped out new Tri Glides for the newer liquid cooled head models.
A fiberglass shield attached on the inward part of the radiator, at perhaps 55 degrees of angle might help. Running full synthetic oil might cut a couple degrees. My Concours was not as effective as the Goldwing at moving heat away from the rider. But, it had two reversible wings to move more heat away, or toward the rider.
I can imagine a scoop, made of fiberglass, made to force radiator heat firmly away at a standstill on the R3. I do not think radiant heat from the exhaust manifold will be a big problem.
Phoenix finally has an at least adequate freeway system now. You can loop around the entire metro area, and never see a stop sign. This will keep you mostly on the move, and I expect you will find it better than you recall. You can jump off and spend minimal time creeping along on surface streets.
The "heat island" effect is somewhat worse, due to the ever expanding metro footprint. Amazingly, up here in Oregon, I welcome the heat off the R3.
I do not envy you headed back to Phoenix. Best wishes. At least on the Rocket, you can wrap up some brats in foil, affix to exhaust manifold. They'll be done to a turn commuting home in July.
