We have cruised many times before, but only once with NCL. We flew in to Barcelona the day before the cruise. I had made a hotel reservation at the Silken Gran Havana hotel. We got there at 8:30 in the morning, so of course there were no rooms available yet. They held our luggage for us and we went down La Rambles, which is the main area of stores and restaurants. The hotel was very clean and modern. The staff was nice and upgraded us to a room with a balcony, which was extremely nice. I would certainly recommend staying here.
Embarkation- We got on the ship at about 1p.m. Embarkation was easy. There were no lines and we ate lunch at the buffet. Rooms were ready about 2pm. One suggestion I would make...they have a few duty free shops where they sell liquor and large containers of water. The water was much cheaper than buying it at the ports. If you buy wine or liquor, just bring a carry on bag to put it in and they will not stop you from bringing it on. If you carry it on in the bag that the store provides, they will confiscate it before boarding.
Room - We had a balcony room on deck 10. It was compact, but we loved the balcony, especially for this cruise. It it so pretty to see the ports and sit on your own balcony with a glass of wine and some cheese.