That would be my plan too with a group like that. You likely can get free shuttle to the hotel from the airport and then arrange a van to take you all to the port in the morning. The problem with using the Princess bus will be you have to return to the airport in the morning, find the Princess rep, and wait on the bus until they have a full load. For probably the same price or less, you can just have the van take you from the hotel to the port. I cant imagine the van costing more than $175 each way for the group, and even if the price was the same, the convenience wins hands down. I would be less averse to using the Princess transfers back to the airport after the cruise, as the buses fill up quickly and they are on the way.

I imagine as time goes on, and the local hotels get used to regular cruises from Bayport, more will start to offer transfer options. Similar thing happened in Baltimore when Carnival came to town in 2009. It was hard then to find decently priced hotels that had transfer and even parking packages, but now there are many options.