We just completed the 12 days Costal Express on trollfjord.We had an arctic superior room, 150 sq ft. I agree that it was cozy, but we did have enough storage. One side of the bed required you to get in bed facing the wall or you had to back up and try again- no room to turn around!
We did book one excursion independent of the ship in Alta. It was a sleigh ride with the small polar horses.I think it was about $150 each, compared to a similar excursion provided by Hurtigruten for closer to $400. It was a highlight of the journey. Pick up and return at the pier.
Experiencing polar dark was as much fun as seeing the northern lights for us. We could certainly see well enough for walking around.
We found that all the staff were great.They were funny and joked with us, knowledgable when giving briefings, and great whenever we interacted. We were blessed with calm seas and no rain, just the lovely snow almost daily.
Good advice about the dry heat- I could not drink enough water the whole journey, but it was made worse by wearing a motion sickness patch. Once I took that off, it was better.
12 days was almost not long enough!