First time on HAL but have cruised with Celebrity, Carnival, Royal Caribbean and Norwegian in the past. We are both ~60 and were in the youngest 10% of the passengers in my estimation.
This cruise itinerary was great for introducing us to the Nordic countries. The length was appropriate and the choice of cities what we wanted. The only improvement in that area would be to drop Kiel and replace with Oslo or some other Norwegian stop.
The ship itself is very nice, new and modern. We had one of the small suites as an upgrade, but to be honest, it was not materially more luxurious or spacious than a normal balcony cabin in my opinion. Bathrobes and binoculars to use were included. The bed was very comfortable, the TV large. The seating area and small side table need an ergonometric rethink. However, the bathroom was the nicest we've ever had and the shower was positively one of the best I have ever had, in any ship, hotel or home! Great pressure, volume, temperature and space. The public spaces on board are tight in some areas (seating around pool, entrances to main stage, Dutch café and the music venues) and oversized/underused in other areas (a couple of random bars, Club Orange dining, 'art' gallery, spa...). Given the target market group for expensive cruises to cultural places (as opposed to the Caribbean booze cruise crowd) and the large number of scooters, walkers and wheelchairs, a more open plan might work better. The sliding roof over the pool is very nice to allow for all weather use of the Lido deck.