We have booked an eastern cruise, our 2nd one. We booked St. Thomas as to be able to take a boat ride to St. Johns so we can hke in the National Park. We did visit St. Johns before but had very little time. The Mariner of the seas stops at St. Thomas and it is, as far as I can remember, about a 30 minute boat ride to St. Johns. The Mariner Is docked at St. Thomas from 7am till 6PM.
We also have been to Nassau and snorkeled at the blue Lagoon. I will not do that again for the rocks at the Lagoon are terriable. Several people including myself were bleeding due to being tossed around by the waves onto the rocks. Once you get past the rocks it is nice.