Funny - I fish mostly in stillwaters (including ponds) and am very, very comfortable with it. I love being the sole element responsible for any added movement to my flies.
That damn moving water is tricky and difficult and unpredictable!
If you want to virtually guarantee to catch sunfish (bluegill, pumpkinseed, redears, longears, green sunnies, etc.) the #1 fly I use is actually a trout fly -- the partridge and yellow soft hackle. Panfish are bug eaters mostly anyway, and these flies imitate a broad range of food items and generally slay the fish around here. Actually, panfish are just as much a "fly rod species" as trout IMO. Oh, and I'm usually fishing them tied on a #10-14 hook -- wet fly style, no barb.
I use no indicator -- just pitch one to a likely spot and use a series of little 1" strips (very small -- not for "swimming", just think "vibration"), but I use the rod instead of the line hand. Just a series of "seizures" or "convulsions" with the rod, followed by 1-2 second pauses (and collect the little bit of slack line), then repeat. Usually a fish hits on the pause.
Soft hackles catch like crazy around here -- sometimes even when other flies like poppers don't work. I fish them with 100% confidence and usually have a box full of them. Some with pheasant tails, some with dubbed thoraxes, and a few with herl bodies instead of floss. Some I use bead heads or copper rib wraps, or even copper bodies like a brassie. They all work.
But, no one uses them for warm water for some reason. Just viewed as an old-school trout fly I guess.
Poppers, worm patterns, various nymphs, and clouser/other minnow patterns all catch the species you mentioned. Try them and see how you do!