It seems that most of the flies I use and see used are weighted or subsurface flies. Are floating flies used for reds and trout (or anything)?

Some guys actually only use poppers/dries/topwater flies for fishing, whether that be freshwater or salt.

Several good topwaters available for trout and reds including VIP and small hard-bodied poppers. They can be very effective at times and are fun for trout under the lights at night.