I've always found one day at SeaWorld to be enough per trip (we did 2 days one year but only because SeaWorld was offereing a get 2 days for the price of 1 deal). You do have to plan out the shows well though. First thing in the morning we ride Atlantis, then we go to the early Dolphin show, then Clyde & Seamore, then Shamu. Sometimes we ride Wild Artic after that. Once we have all of the major stuff out of the way, we then have a relaxing lunch and enjoy the walk through exhibits and some of the less crowded shows. If you do it this way, you can usually do everything 1 hour or so ahead of the rest of the crowds. Also to get there from the hotels, we have MEARS shuttle pick us up. You give them a pick up time for early in the morning (we try to get there 15 min before the park opens) and then you call them about an hour or so before you want to leave for a pick-up time. Hope you enjoy SeaWorld!!!