I'm using a Royal Wulff triangle taper line on my 4-wt. I can't tell you much about what advantage a triangle taper is supposed to provide, but I like the line a lot. It's on the higher end of the price scale, but I'm inclined to spend more on a good line as compared to other components of a fly fishing outfit for trout.

I would add to the list of SRC flies anything that resembles October caddis, in any stage of its life cycle. An orange stimulator works for the adults, but the nymphs are usually darker in color. Especially from September on, it's all about the October caddis; I've seen coho rising to them before when a good hatch gets going (only once, but hey, you gotta admit that's food for thought).