Once again ,I have not done the Princess excursion. Pali lookout is a beautiful sight, high above Honolulu with breathtaking views in that direction of the island. A bit windy here to say the least so leave your hat in the bus.
Dole Pineapple plantation is on your way to the north shore. It is a pretty, if not fairly commercial, stop that provides for a few good photos, some shopping, clean restrooms. Try either the pineapple whip, which is like pineapple flavored soft serve icecream and is to die for, or, buy a plate of fresh, (you will never taste better), pineapple.
If you are going this way to the Cultural Center you will also ride along the highway that passes all the famous North Shore Beaches. Ride on the left side of the bus to get the best views.
Mormons run the Cultural Center and the Temple is located next to it. This should be an interesting experience.
Have a nice time on your excursion.