Good morning, Bruce;
Will the main vehicle be the Pride of America by any chance? The list of islands sounds awfully familiar. And, now I can definitely state that there really is a difference when you go to sea on a ship that is not painted all over in grey paint.
While on Maui, take the "Road to Hana" trip. There are a couple of stops along the way where churches meeting your description can be found. And, the van will go all the way around Haleakala; the road on the south side of the mountain has really been improved, and it is no longer a "four-wheel drive vehicles only" road. Hasegawa's General Store in Hana is worth the visit and photographs. There are lots of things to see and history to be noted.
And, when you are coming into the harbor at Lihue, Kauai, take your camera up on deck with you. Watching the Captain shoehorn that 860 foot long ship through the Nawilliwilli Channel to get into the harbor is impressive all by itself. Tug Tiger-8 may be there to help.
When you are on Oahu, and the if time is available, going to the Arizona Memorial and BB-63, the Battleship Missouri, is worth it. It is appropriate that we have the beginning and the end for us of World War II there together at Ford Island.
Enjoy;
Ralph, whose personal history with Hawaii includes 1 year, 365 days, 16 hours, and 2 minutes, spent on Oahu back in the 1950s.
Latte Land, Washington