Yeah, the Gulf Coast of Florida is a bit nicer than the rest of the state as the water is calmer, warmer, and the sand is nice and white. The Atlantic coast definitely has it's advantages too, the waves are nice to body surf and some of the old towns are really charming.
Nearly any beach from Clearwater Beach to Naples is great, there are great party towns to quiet fishing towns; so something for everyone. My favorites are Madeira Beach, Sanibel, Naples, and Cedar Key. Cedar Key is not really a beach town, but it is an island with old buildings, fishing, and no chain restaurants or hotels, it's a real "old" Florida town.
North Florida has a lot of great beaches too, and since it is 3-5 hours closer to the rest of the country - it is much easier to get to. I'm not super familiar with most of those beach towns though. I do know that St. Vincent Island (off of Apalachicola) is where Red Wolves are raised. It is one of only two places in the world to see "wild" red wolves, along with a reserve in North Carolina.