Panama City Beach, Destin, Orange Beach. All worth visiting for beach activities, can't attest to others. We've stayed at all except PCB and probably will next time. Other than Destin we've always gone off season for a warm(ish) weather break from Indiana winters.
Key West is a different world the best time of which to visit is Fantasy Fest but you must have a VERY open mind for that scene!
Just watch out for this guy.
WTF?
Go G8TRS!