I have stayed at all 4 properties - RH, Sheraton, Moana Surfrider, and Sheraton Princess Kaiulani.
RH - the best. i like the breezy common grounds and the access to the beach. They usually have some chairs and stuff for RH guests. it's relatively quiet compared to the other properties and has a nice luxury feel to it.
Moana Surfrider - i like this 2nd best. it's a little busy and there are always a lot of people walking around in front of the hotel since it's right in the middle of the shopping part of town. but the lobby is nice and the grounds are nice. i like the bar and they have live music at night. beach access is nice but gets crowded.
Sheraton - they have the best pool. It has a nice slide. access to the beach is also nice since it's right next to RH.
Sheraton Princess Kaiulani - i try to avoid this hotel. the pool is nice but you have to walk a bit to get to the beach which is a pain. the lobby and common areas are always packed full of people (mostly tourist groups from Japan). the room feed dated.
For a honeymoon I would book the RH. if that fails, i'd go with the moana surfrider.