I also use a six weight rod for smallmouth. I usually use a nine foot knotted tapered leader going down to three x which is usually eight pound test. I have trouble turning over some of the bigger hair bugs and poppers so I will cut the leader shorter and have about a six foot 1 x leader that can easily be restored by re-attaching the segment I removed. In the rivers I fish I don't feel the need for a sinking line but I do carry a few heavily weighted flies as sometimes is is dredge the bottom or just have casting practice.