For my husband and I, we go MAINLY for the ship. He has had several melanomas so we try to stay off the islands as much as possible. We LOVE the ships though.
As far as Key West..........I would LOVE to go there and wish RCCL would add that stop in their schedules. It would be one more stop and the Eastern Voyages of Liberty (for one) only stops at Labadee, San Juan and St. Maarten. They could add Key West in on the trip back.