I think you need to decide if itinerary is more important than the ship.
We don't have date pressure(same year is good enough) so can be a bit more flexable.
Could go twice once for the ship once for the itinerary.
With any Med trip you can cruise only and organise your own flights pre/post cruise often a lot cheaper
Some agents package their own flights not the cruise lines.
For Barcelona we like the early BA heathrow flights no pre cruise night needed and on the ship for lunch.
Other med ports often need the pre cruise night.
If the plan is to cruise more often then trying to make this one perfect is potentialy a mistake.
Sooner or later one of the future ones, that was going to be just another cruise, will be better anyway.
So I would focus on one aspect that will make it special.
The Equinox is probably the best choice of ship, HAL the best itinerary.
It's going to be hot in August so a few ship days might be a change from being a tourist in the heat.