We were on the Star last June to Alaska. You will love this beautiful ship!
The bathrooms are not spacious but they are laid out differently than other ships. As you step into the bathroom the vanity is in front of you. I think there were 2 long shelves underneath the vanity with room below the bottom shelf for other things.
To the left of the vanity is the toilet which can be a separate room if you close the pocket door. It would be tight quarters with the door shut and we always left it open. If you HAD to have privacy and someone else was in the bathroom you could shut that door to the toilet.
The shower is on the right of the vanity, with a glass sliding door. It is a very nice shower for a ship. Plenty of room in there, with an adjustable, removeable shower head (Grohe no less) and the usual soap and shampoo dispensers.
As for storage, we thought there was very ample storage. Plenty of closet space and we had plenty of hangers. I have heard others say to bring your own hangers but we didn't need to this time. Inside the closet there were some shelves, and a light, which was a nice touch.
In the hallway, below the fridge there were 3-4 drawers that were plenty big enough for lots of stuff. There are also open, exposed shelves in the main part of the cabin for other things. There were 3 of us in an outside cabin and we never had a problem with being cramped, or having enough room for all of our stuff. And I'm not known as a light packer!
Good luck and I know you will have a very nice cruise on this beautiful ship.