I will place emphasis on the cruise portion. With a group reservation the tickets were waiting at the pier and we quickly boarded. Our cabin number was only then provided based on the chosen category. My cabin proved to be a problem because it was next to the loading ramp and by the laundry room. There was little chance to change the cabin as all cabins were booked well ahead.
The Ms. Polarlys is a typical fleet ship with about 550 passengers as well as cargo and ferry service. The ship kept tightly to schedule and stopped at about 34 ports (same group) in each direction on the round trip voyage. Day and night schedule alternated. The departure date was on the Winter Schedule and just before the switch to Summer Schedule. This limited some stops and excursions.
All meals were included with the package. Breakfast and lunch were buffet and open seating. Dinner was a fixed (feature) menu with reserved seating. It would be very costly to purchase the meals on your own. The food was varied and typical Scandinavian with lots of fish but plenty of choices. Reindeer was presented, too. Cruisers with dietary concerns were accepted but the menu was limited.
The cabin was smaller than some ships but fine for me. I had a futon style bed by the window and fold down bed from the wall. There is a small desk. Power is controlled with the room's key card and there is both 220 and limited 110 ac power. Linen/towel service is on demand or weekly bed change. There are no televisions in the cabin. A phone with radio was in each room. For two people, the storage space might be tight. The bathroom was good and water temperature is great. In rough weather there is some water noise. My cabin had a window and seemed close to the sea (on deck 3).
Decks notes: Deck four has the dining room, snack area, Internet room (free for many users), tour desk, bar lounge, child play area, meeting rooms, shop and viewing seats. Deck three is the service desk, laundry and most of the gangway use. Deck five is the boat deck and outside viewing in some sections. Deck seven has the panorama lounge, bar lounge, library and more viewing areas.
Other passengers without cabins, slept on overnight portions, in the viewing lounge and the library. Some children were along but I might not be sure that all tourists would want their children along on this trip. Announcements were usually in four languages as needed: Norwegian, English, German and French. The currency on board is Norwegian Kroner or an arrangement with your credit card. Americans will be frustrated with what we see as high costs and as compared to our money and economy. English is commonly spoken.
The scenery is the prime entertainment. If you take photos, be prepared to shoot through glass (often dirtied by weather) or be dressed to go on the outside decks. The weather will have great effect.
The trip can be very relaxing in most cases with plenty of time to socialize and watch the "world's most beautiful" scenery pass by. Don't expect a fancy, upscale cruise line arrangement. This is a great trip for those who want the adventure and experience. I am sure that I did not tell all here so I may be able to help your questions but do the research, too.