Forget the V8 Tundra. You'll spend more in gas, GVW tax, and (most likely) maintenance. Besides, Toyota has been making great V6 and I4 engines for a very long time. They're more reliable (especially the I4) than any other gasoline engine made.
I've been in the Rockies for 37 years, have owned 3 Toyota PU's with the I4, and I've never complained about the lack of power. How fast do you have to go, anyway? The views are great - relax, enjoy the ride, and don't worry about the few minutes you're losing over the course of a few hour drive. Besides, aren't you in the dirty-D? You're in 'stop and go' anywhere within 100 mile radius of that place - I-70 westbound on a Friday afternoon, anyone?
It'll also be easier to find a I4 in CO than a V6.
Oh, and about the warped rotors - this will happen on any vehcle that's driven improperly in the mountains. Lay off the brakes already. You have gears to regulate your speed going downhill.