Since it may be a once in a lifetime trip, don't miss the chance to go to Pearl Harbor. Study about the attack a little before you go, and recall all of that while you are standing on the memorial over the sunken remains of the USS Arizona. That was the start of the war for our country. Sitting a few hundred yards behind the Arizona is the ship that represents the end of that war, the USS Missouri. The Japanese surrendered on the Missouri.
There are many other things to see on Oahu, and you can get a bus to most all of them. We enjoyed The Polynesian Cultural Center, North Shore, and the International Marketplace. I can't help with Maui, or Kuai. My ex wife lived on Maui for a year after we split up, and said there's a nude beach there....lol. Have a great trip!