We are currently on the Crown on the way back from HI and did the tours on our own. Here's how it worked out for us:
1) Took an Uber ( $25 each way) from the ship to the Bowfin and did the submarine and exhibit tour. As stated above, you will not be able to bring a backpack or bag.
2) Took the shuttle to the Missouri and did their tour, also did the chief engineer tour (costs extra and offered on a time schedule). The MO and Aviation Museum are on base, the shuttle is the best way to get over there. You would not be able to take a rental car there unless you have a military ID. Even then, I would check to see what the requirements are for rental car documentation.
3) Took the shuttle to the Aircraft Museum. There is a cafe there to have lunch at.
4) Shuttle back to the visitor center, Uber back to the ship.
It was a long day with a lot of walking, you would need to be off the ship first thing. We had been to the AZ memorial on a different trip so did not go again. We had been to the MO on that same trip but had to cut our time short because we were on an organized tour so we wanted to go back and see more. We got back to the cruise ship around 1700. Last shuttle out of the Aviation Museum is 1700, last one out of the MO is 1600. MO closes at 1600, AZ and Aviation close at 1700. For everything except the AZ you could but wouldn't have to purchase tickets in advance.
There would have been time to go to the beach since the ship wasn't due to leave until 2300, but we were tired and there was some kind of a festival going on in Waikiki when we were there. If you saw fewer of the museums/memorials you could easily do that in the morning and have the entire afternoon and evening free.