These cruises can be port-intensive, so the right itinerary is not simply the one with the most stops.
Some itineraries genuinely center Greece while others include only one or two Greek ports.
An overnight in Istanbul or another major city can change what you are able to experience.
Rome, Venice, Athens, Barcelona and Istanbul often deserve extra nights beyond embarkation day.
I can check fares, group space, cabin choices and package value for the cruise you are considering.