We just got back from a cruise on the Wonder in 5520 and loved it. We brought a small clip to keep the curtains closed over the porthole and to keep the curtain closed between the queen bed and the space with the sofa and pull-down bed.
There were three of us, and we had plenty of storage room with room to spare. Our closet wasn't even half full, and we never even used the over-the-door shoe holder we brought. This was for a 4-day cruise (which turned into a 3-day due to hurricane!), so you might need a little more space for clothing on a 7-day cruise.
If you have any other questions, feel free to ask.