I have done Eden Rock & the Stingrays. If this is your first time in GC, the stingrays needs to be your first choice. It is a fabulous experience! Eden Rock is nice, but the stingrays are much, much better. You will never be closer to stingrays in your life, unless you go to Shark/Stingray Alley in Belize.
Our first visit to GC, we did the Island & Stingray City tour through the ship. We went to Hell, the Turtle Farm, Stingrays, & still had time to shop when we were done. Our second time in GC, we just went to Eden Rock, Hard Rock Cafe, & shopping. Third time to GC, we did the Atlantis Sub.
Have fun!!