Working the water column top to bottom...
Surface: small to medium sized gurglers - white
Shallow 1: Medium sized Murditch minnows - white (sharpie colored top, gray or tan)
Shallow 2: cone head wooly buggers - all white, olive, tan, or black
Deep 1: small to medium sized Crayfish-ish patterns in tan, brown, olive and combos of these colors
Deep 2: Clouser deep minnows - chartreuse over white or 1/4 olive over 1/4 chartreuse over 1/2 white (tri-color)
Retrieves are the same for all three: one or two strips then pause. Takes are mostly on the pause.
NOTE 1: I always have some flash on my flies, even the gurglers and especially on the minnow-imitating flies.
NOTE 2: In low water of late summer I like to fish an all white Murditch minnow so I can see the takes. Smallmouth are very aggressive when properly triggered. This means adjusting retrieves to suite the water temps and conditions. Patterns are far less important, more for angler confidence.
Depth control is also key. If you are fishing subsurface and either never hitting bottom or constantly getting hung up, change the weight of your fly. I tie so I can alter my patters like this:
1. use heavier or lighter dumbbell eyes
2. add or remove material to affect hydrodynamics.
So, whatever retrieve speed the fish want, you should have flies that get tot he appropriate depth and that changes often on the rivers and creeks.
DISCLAIMER: I am a chronic fly changer. My fishing partner changes flies rarely and it's almost always a gurgler or crayfish fly. We usually catch the same number of fish. That should give you a little hint...