The thing about Hawaii is that you want to get away from the port area and out onto the islands.
In Oahu the port area is a brief cab ride or even a bus ride from "downtown" Honolulu and Waikaki beach. The same can be said for Pearl Harbor. North shore, Polynesian cultural center, Haunama Bay, Lanikai Beach, Paili lookout, Dole Plantation Etc. All need a car or bus to get to.
When you say Hawaii and you name Kona seoerately I presume you mean Hilo. Not much to see in the immediate area of the port. Volcanos, beaches , orchid farms, Macadamiia nut farms eyc require a car or a tour.
You don't say what ship, so hard to say where you are landing in Maui. Some tender right into Lahaina and this is a center for much of what there is to do on Maui. Some dock in the town near the airport. Great if you want to go to Walmart but not if you want to see Hana, Kanapali Beach, Lahaina, Wailea, Makena, Iao Valley, or Haleakala. You will have to take a tour or rent a car.
Kona is a tender port and you do tender right into town. There is shopping etc but if you want to snorkel , go to the beach or sightsee, once again take a tour or rent a car.
In Kuai you land in town and can cab to shopping . Napali coast, Poipu Beach, Fern Grotto, Waimea Canyon Etc Etc will all take a car atour or even a helcopter.
There are rentals in every town. Often book up 100% and remember to leave an hour to get the car and 90 minutes prior to sailing to get rid of it.
Tours are often your best option in the ports in Hawaiian Islands.