I was on the same cruise as Pooh1Bear and also rented a car in each port and did the 3 days precruise in Honolulu. Just 2 cautions. In Maui I drove up to the vocano at 10,000 feet and it is a draining criss-cross drive. After decending, we then did the drive around the eastern coast of the island. The highway is very narrow and taxing to drive. The northern portion is a very good highway through the rainforest and the sights are amazing. The sourthern route has a terrible highway and is not worth the journey. Some rental car companies tell you not to drive this. There are no service stops and if you need a rest stop you will have to hold your breath. Drive the norther n route until you've seen enough and turn around and go back. There are some excursions that do the entire coast line.
In Honolulu I went to the Paradise Cove luau and was disappointed in it. Do the one in Maui if you want to do one. Enjoy your cruise.