I was disappointed in many aspects but perhaps my expectations were off for a European line. I haven't cruised that much, I went for the scenery (Fjords) and convenience of a cruise. I was taken aback by how much Costa pushed the bars and the drinks. They did a good job on some other things, but it was clear where their priorities lay.
The shore excursions were generally good.
The dining room food was very good, but small portions, so order a lot.
The self-service restaurant food was very good at lunch, but severely limited between lunch and dinner. But often too crowded and hard to find a table.
The wifi was terrible. Pricey and poor quality, could only surf, all uploads failed.
THe library was barely adequate.
The Costa people were nice, but the other guests were generally quite rude. Probably standard fare for European cruise, but don't expect people to respect lines, or let you get out of the elevator.
Quite a bit of smoking, it is allowed indoors on the ship too.