Yep, I agree..you can do all three islands on your own..easily.
Key West...be prepared..have your plan..there are some great things to see. You can take the trolley/little train tour on your own..at your convenience. You can also..rent one of the space ship looking golf carts and make your way around..they have 4 seaters. The people that rent them are great...we booked for 4 hours...we got done in two..decided to turn cart in early..they just changed the contract so we only pay for two hours...we didn't even have to ask them to do it..they were just concerned when we pulled in that something was wrong because we were back early. Very nice people. We rented it right on the corner near the Pier House resort at 1 duval street..short walk from the dock. We drove to hemingway house, southern most point, Bo's fish market..if you are eating in key west..stop there..best fresh fish sandwich ever. And you can also get fresh conch fritters, if you haven't tried them, it is a must while in key west. After we turned the cart in, we walked to some of the close places, did some shopping and then back to the ship to watch the sunset from our balcony..it was excellent.
In Grand Cayman...we wanted to see the major attractions before having lunch and doing a bit of shopping..so when we got off the boat..we looked for a taxi..they offer tours for about $15-$20 per person..can't remember exact amount...takes two hours..they stop and let you out at hell, the turtle farm, will drop you at a beach on the way back if you want..a nice tour of the towns major attractions and such..well worth it. Stopped at Rackhams (ocean side a bit up from the dock) to have a stingray beer. The food looked great, but we had already chosen a lunch place. We will definately eat here next time. This past time we ate at Big Bamboo. Great fresh grilled sea food. Both places had wonderful people to enjoy and the decks overlooked the ocean at both places..excellent. Very relaxing and not to busy. Rackhams also has a great souvenier shop..we did our best shopping there.
In Cozumel..again..all on our own as it was our first time to this island. We had ordered our map and had our plan all ready to go.
On the suggestion from cruisers before us..we debarked the ship and grabbed a cab to Mr. Sancho's beach area. It was wonderful, the food, the service all excellent. The beach is beautiful, water clear. Hubby said he could have spent days there. We were in relax mode..but, there was plenty to do if we wanted to do it. We spent 3/4 hours there then grabbed a taxi back to the dock/shopping area. We had the taxi drop us at the far end (not really all that far) and we walked our way back to the dock. Don't forget your coupons for your free diamond earrings and tanzanite earrings from the Forum shops if that is still being offered when you get there...small stones, but, fun to get none the less. Great humidor upstairs if you like cigars, great jewlery store downstairs. We also walked about two blocks more..away from the dock, on the recommendation of the people inside..to the grocery store to purchase our tequila and vanilla.
We took all our packages back to the ship, freshened up and came back out for dinner at Carlos and Charlies..great food and service..right across from the dock, front open to the outside.
Enjoy!