I used to go to a CME program at Tradewinds. I wouldn't mind going again, but it is always the week before spring break. We stayed at a different property that used to be affiliated with the Tradewinds, and we used to be able to sit on the Tradewinds beach and use their facilities. This was sold several years ago, and I am not sure of the arrangement now. Since we like to sit on the beach and look for shells, Tradewinds suits us. They used to have a lot of children's programs, also. We liked going to a bird rehab place nearby, and the aquarium, and other things like that. My husband's family also lives nearby.
Personally, I really liked Sundial at Sanibel. Sanibel has Ding Darling reserve, and if you walk along the beach, it is possible to get some awsome shells and see some interesting wildlife. St. Pete Beach, not so much.