The bluegills around here seem to prefer something with yellow in it as opposed to white. They aren't too picky, though, in my experience.
For trout, I love to fish parachute ant patterns. They almost never fail me, despite whatever else may be hatching or otherwise on the surface. Grasshopper patterns are pretty similar in performance.
All around, I like a parachute adams or PMD. Wet flies I like the Hare's Ear or generic "little green nymph".
Regards,
