In my region - just a couple of miles from your's - I love floatubing and bellyboating in small high mountain lakes. My favorite combination there is a 4 or 5wt, intermediate line and long (4x) leader with a Partridge & Orange soft. Just casting close to rushes and sunken logs and the strikes of (mainly) brookies and rainbows begins. I conisder the Partridge Series a killer fly everywhere and many times I get bites during the time of the slow sinking.
R