A new clean hotel on the beachfront less than 5 minutes away from the ferries.
Upon arrival we were greeted by a friendly staff that notified us that our basic room was upgraded to a premium terrace room, the best cathegory in the hotel. It isn't usual in Italy. The room was large and spotless with a very large terrace right on the water. Very nice bed and bathroom too.
There's a rooftop bar that was unfortunately closed due to "cold weather". The next day, however, there was a jazz band playing there. 1 minute away is a very nice bar Gusten that closed at 3am. All the best restaurants are within a 5-10 minute walk.
Breakfast was alright. Poor by mainland standards, but decent for Sardinia. In fact, if you haven't been to Sardinia, you should also know that hotels usually don't provide hair conditioners, paper towels and have a checkout at 11am. Nor do they collect city tax.
Overall, we have walked around a lot and I am quite confident that Riviera hotel is by far the nicest on the waterfront.