Well, I can't help it, the extra day always wins for me
On our first trip to Dominica, we did exactly that. We snorkeled in the morning, our cab driver came back and picked us up around 11 and took us up to Trafalgar Falls and the Emerald Pool. When we were there, they hadn't built the cat walk out to the snorkeling spot, so you had to walk over boulders to get there. By the time we got to the falls, I was too worn out to hike. I stayed on the observation deck and drank a bottle of water while my hubby went on the hike. He said the Emerald Pool felt great after hiking down, but then he had to hike back up and he was totally worn out! I'm glad I just sat back and watched, my feet were killing me
St. Croix is much more like St. John than St. Thomas. I really liked St. Croix and was hoping they'd add it back. I don't know why they ever stopped going there, maybe it just wasn't deep enough to handle to larger ships?