Just to clarify, I've just noticed that I put we was flying home from Fort Lauderdale when it is in fact Miami. I've had a look at a cab comparison site which indicates that Lyft will charge £64 for the Ship to Airport transfer. According to My Viking there's not any optional excursions for the last day. I think we'll see what Viking will charge for arranging the transfer when we're aboard, if we can't use their shuttle that is, and if it's not an exorbitant price we might go with that.
We'd much rather have peace of mind, on our first cruise, than worry about saving a few pounds .