Unrelated to this debate that seems to crop up now and again, and part me hesitates to ask you considering the directions you could go, but have you ever heard of microfishing? This has recently piqued my way interest. Basically the goal is to catch the smallest fish you can, and as many species as possible. I find it interesting because it opens up old spots to new possibilities. Tiny streams that might not be big enough to hold trout might hold dozens of minnow, dace, darter, sculpin, etc., species. It seems you use the lightest rod you can find. Some people use rods with no reel, some spool up a tiny reel with 8x tippet. A lot of people make their own dough bait for it. I have the gear for this, but I never really thought to purposely pursue what would normally be considered bait fish. But there has got to be some challenge there. I'd imagine darters would be particularly tough to catch. And some of the breeding males of certain darter species have incredible colors rivaling many saltwater fish species.