We celebrated our 30th wedding anniversary this year by cruising Alaska.
Only been on Carnival before, can't say I was over-impressed with Norwegian but had absolutely no complaints. Totally personal preference but I'm not sure I liked the freestyle dining, thought way too much emphasis was placed on the specialty restaurants.
Also did not get the feeling that we were "special/remembered" like when the staff remembers your names or your drink orders. Again, still received quality service with no complaints. Room was always taken care of, never had to wait in line really at a restaurant. The ship was pretty full and only had slight issues with finding a table near the buffet.
Pretty standard ocean view cabin. Small but enough room for just the two of us. We decided to forego the advice to get a balcony and spend the money on excursions instead and we did not regret it.