We liked the beach and the picnic that the ship provided was fine. Be sure to find a covered area out of the sun and bring plenty of sunscreen. The clamshells were mostly gone when we arrived.
My children took a cab to the Sheraton Resort. It's on the other side of the island. They felt they had a wonderful time and that $25pp was quite reasonable.
We enjoyed our excursion to Atlantis.
We chose to take the shuttle to Cocoa Beach and the mall. It costs $9 rountrip. Don't let the cab drivers hassle you. The shuttle runs every 20 minutes. Follow the crew. They use it all the time.
My children rented a car and drove to the space center. They had a great time and the cost of a car for the day was only $20.