Don't forget soft hackles. I'm not much with dry flies, but in the early evenings, when I hear the water bubbling, I start swinging soft hackles of all sizes and shapes. Probably do best on #14 and #16, browns, grey, purple and orange. Experience, and alot of reading has taught me when I see all that surface activity, alot of is is actually subsurface, sipping bugs in the film or just under. The only tough part when the water is low is finding spots with enough current to get a good swing. Hang on because the hits can be hard.