I guess it comes down to why you cruise - for the voyage or for the ports of call. The typical cruises out of Australia follow a circular route around the South Pacific & there really isn't much variation between ports. So shore excursions become of less importance than they appear to be in the Caribbean for instance.
I'm a believer in "The Cruise" as holiday not as hard work so I prefer a low key brief on exchange rates, good beaches, indiginous markets & local highlights. But I don't believe in 2-3 hour bus trips or conducted tours of the shopping centres.
But we go to have a good time according to our own desires & I have no beef with others who choose cruises by itinerary rather than by days at sea. And I have to admit to planning the Coastal Voyage ex Bergen to North Cape & it's hard to imagine a more destination intensive cruise than that (25 ports in 11 days)