There are a number of good sand flats along the Gulf Coast that are wadeable.
You'll need to up-grade your gear for saltwater. An 8-weight rod and corrosion-proof reel should be adequate for the conditions you described.
Plan on doing a lot of sight casting. Also be prepared to make longer casts, ie 40 to 60 feet, with weighted flies.
In lieu of wade fishing, consider a canoe of kayak. A number of folks in FL are giving up on the expensive flats boats and going the way of canoes of kayaks.
Tight lines.