One of my fellow camp hosts in the Greater Yellowstone used nothing last summer except traditional wet flies or a hair wing form of them. He did fantastic using them as searching patterns in some heavily fished waters. I've even tied up some Grizzly Kings, Professors, etc for my trip west this year. Got looking at Ray Bergman's ties on Flytyingforum.com.
In the Smokies, I found that fishing a slightly weighed Quill Gordon WET as a nymph and letting it swing at the end of a drift is a KILLER!! A March Brown Flymph is great also. My Quill Gordon WET is the only tandem rig when I use one. I tie it off a Dry Mr. Rapidan or Parachute Adams. (I've found that I snag up in the trees enough with ONE fly, so I usually don't need two(:>). If I get a chance to get to the park this spring (got to have my campground open before Memorial Day) I'd definitely start out with those two.