Its good that you've identified some things you want to do. I'd suggest that day 2 should be a day at the resort. You'll still be adjusting to the change in time and the flight so some time at the pool will probably be nice.
As far as Pearl Harbor goes - yes, that's a must do. I'd suggest you do it on a day that the flea market at the Aloha Bowl is in operation (Wed, Sat, Sun) which can be a fun, cheap diversion.
The Dole Plantation is very much a tourist trap. Go with that in mind. Wander the grounds. Take the train. Get a dole whip. Buy the t-shirt. Check the box.
I don't see Diamond head on your list. Amazing place. Include it on a drive around the south east side of the island. Stop at the blow hole along the way around. Take the H3 through the mountains. Breathtaking scenery.