Easy! Number ONE for me would STILL be the Yoshi's Samurai in #16, its chestnut red colouration is a fantastic representation of small stream mayflies, it's heavy and small, sinks fast with its quill body! It has an epoxy wing case with a thin tinsel strip. If I'm fishing rainbow waters, leave it on... brown town, snip it off…now that's a customisable fly!
Number TWO and a new favourite on small local streams is the Smethurt’s Baetis Bomb in #18. This thing is AWESOME!! So small and heavy to get down to tricky fish fast, it's so stealthy, yet an absolute hunk of tungsten. It really is a fantastic fly on well-fished-over trout! You HAVE to try this nymph! It also is tied on a really strong forged hook, very important when fishing 18's.
Number THREE would be the old Parachute Adams. Call me old fashioned, but as an indicator fly and late season dry, it can't be beat! It will pull fish from fast or slow water with more charm than a horny teenager. My fly box is full of Manic Parachute Adams with white and pink posts. It's the only dry to use locally late season, or in fact the whole country over!