I'm surprised that Ravenna is building a new port. I've read reports where other port cities are trying to cut back or even eliminate cruise traffic.
You should consider the kind of destination. From US, Ravenna (and Romagna in general) is not known as perceived like a little and not important destination. For Italians Romagna is the most important beach destination and every Summer are gathered there 4 millions or more tourists (15% foreign tourists).
A ship who dock with 5000 people landing doesn't make a great difference, even if should be one ship every day.
What is very interesting is that Romagna during 20th century was able to create a huge mass tourism system without losing his soul and create a huge network of several little entrepreneurs. Most of the hotel are still family run!
It seems odd to me that cruise ships would use Ravenna as their port so that the cruisers can go to Venice for the day.
Is a Venice problem: the great ships are creating pollution problems inside the "laguna", so they must keep ships outside it. The solution was to build a brand new dock offshore, far from the lagoon, or using an existing one. The two closer are Ravenna and Trieste.
In the last tens of years has been closed all the industrial activities and commerciali ships movement inside the lagoon, not only the cruises.
What so many posters on here forget is that provides employment for the local bus drivers, and also for the guides.
That is true. The most of service providers are local ones: local bus companies, local drivers, local guides. I have several colleagues who work with cruises. Again: remember that there are about 50/60 cruises a year, so a guide cannot work only for cruises: is one of the several guided tours a guide do for his job.
In general cruises groups are not so different from other groups: is easier that in a big group there are more people giving problems (arguing, claiming for some reason and so on): mainly if is a daily tour when a guide hasn't the time to manage that matters. But is part of the guide job. And (from another point of view) is part of the skills of a guide prevent that kind of anxiety.