Having enjoyed Princess Cruises before and taking advantage of a Black Friday deal, our family decided to embark on this Diamond Princess cruise. I highly advise spending time in Tokyo and Yokohama before departing, as there is so much to see and do there. We went to museums, shrines, shopping centers, and even Disney beforehand. There's something for everyone in Tokyo, which may not be the case once you get on board and start visiting the ports.
Embarkation was terrible. Half our party received an email that departure was delayed and half didn't, leaving us in a foreign country trying to figure out if it was a hoax or not. Then we were left in the hot and humid cruise terminal for hours waiting to get on the ship. Once on the ship we couldn't even get something to eat because we had to go directly to our muster stations. Because everything was done in both Japanese and English, this took even longer, which made it very difficult for the seniors and kids who had gone hours without eating or even having water.
Once settled into the ship, we realized that the ship was really showing its age. There were pockets, including our stateroom, that just did not get any air conditioning at all, which when coupled with the 95F weather in Japan was suffocating. About half of the employees were outwardly friendly and the other half didn't speak unless spoken to. The service in the dining room was inconsistent - we often had plates piled up and empty water cups on our tables. The food was okay - try the Italian food - the executive chef is Italian and many of the recipes are his own so those never disappointed. The menus often included dishes from celebrity chefs, most of which were very delicious. I did not have the chance to dine at the specialty restaurants, only main dining and the buffet. The buffet was kept clean and fresh, complete with both western and eastern options. The dining room in the buffet was pretty similar to what we saw in main dining - lots of plates piled up. Because we had ongoing issues with our stateroom, I frequented passenger services a lot. This was a great highlight because they were very responsive and always followed up.
Find a tour guide or do lots of research beforehand because there's so much to see and do. There's something for everyone - history, art, architecture, shopping, food, etc. We were able to eat fresh sushi and sashimi at the fish market, go to an outdoor street market, visit the Tokyo Museum, visit Disney, and see other sites while in Tokyo.
If you are into history, this is the place for you to relive what happened on August 6, 1945. See the remnants of the one building remaining after the atomic bomb. Capture the thoughts of those who lived it at the Peace Memorial Museum. Visit a castle or gardens - these are plentiful and each very different throughout Japan. It is extremely easy to get around via streetcar - there's a one day pass that you can buy for unlimited rides. Again, you have to pay $10 to get to the streetcar station from the port.