We had a fine time on our cruise (thanks in part to the amazing weather), but there are some things that might be useful for others to know.
I encourage you to reserve a time for dining (Traviata and Rigoletto are the dining rooms on decks six and five), even though originally I wanted to dine at will either at the Horizon Court buffet, which is open pretty much all the time, or try our luck at getting fitted in to a dining room for each meal, or explore Cafe Corniche on deck eight (I'm told the pizzas are very good) or the Riviera Grill on deck fourteen for hamburgers, hot dogs, etc. (didn't try this, but heard good things). The food in the dining rooms is very good; the right side of menu (which is also posted outside the dining rooms) is today's particular offerings, while most of the left side is available consistently, so you can find something you want no matter what. We sat with very pleasant and amusing people, which made dinners a high spot in the day.
The only awkward part was that dinner seatings were at 5:15, which was quite early for us, or 7:45, which would have worked out better for us. They will hold your reservation for only 15 minutes, which is fair considering that they need time to serve several courses. They ask that you tell them if you plan to miss a meal. Some people were under the impression that unless they had originally signed up to eat in one of the dining rooms, they were restricted to the cafe, grill, or buffet, which is not the case - just call and find out how to get on the list. For both breakfast and lunch, we also ate in the dining rooms, but not in assigned seats, so I assume these meals are open to anyone as well. We had breakfast a couple of times at the buffet, which was fine, as well as a sushi lunch that was also fine, if not the fanciest possible; some people didn't seem to care for the buffet at dinner. I did not have a bad meal at any time during the trip, and I am still raving about the lamb chops, which were perfectly cooked and beautifully presented. I wasn't as fond of the beef, but loved all the fish I ordered, and the duck, and the venison, and the various terrines and other appetizers. If you find that you have made a mistake and ordered something that you don't like, just ask for something else and they will be happy to bring it - several people did this at our table when a particular main dish was not to their taste.
Be aware that afternoon tea, served at Traviata at 3:30 each afternoon, is not to be missed: scones, tea (good tea, as affirmed by my Brit husband), sandwiches, cookies, cakes, served by white-gloved waiters and accompanied by piano or a string quartet on our voyage. We always came at 3:30 sharp because we would be eating again at 5:15; hence the recommendation for the later dinner seating.
The name and number of the decks appear at the the sides of the stairs, opposite the two main elevator banks - it's not obvious where you are unless you check this location. Study the deck plan beforehand and you will be glad you did - there are two sets of regular elevators and the see-through elevators in the atrium, and not all elevators go all the way up.
Many people are not aware that there is a steam room and sauna in the Lotus Spa in the men's and women's changing areas and that they are available to anyone, not just those who sign up for a spa treatment. See below for how to get there.
Also, there are two nice hot tubs and a small pool aft on deck twelve, which you can reach by going through the Lotus Spa instead of having to walk through the fitness center or going up to the next deck (fourteen; there is no thirteen) and walking down the stairs. Just go to deck twelve, go to the side of the ship where there is a beauty salon on the right and the spa on your left, turn into the spa sitting room and go left to walk past the desk right into and through the spa hallway until you reach the changing rooms, and see the door to the hot tubs on your right. You can take a shower afterwards in the men's or women's changing rooms (but there are no lockers, so bring a bag without valuables in it and leave it in the changing room in an inconspicuous place, as I did, or stuff your spare clothes in your robe pocket and wrap it around the railing by the hot tub). Ask your room steward for a robe; towels are available by the changing rooms, and you can use them and leave them there.
Also, if you find the bed hard, ask your room steward for an egg-crate mattress topper as well as a couple of robes; it helps a bit. You can also check out blankets on deck twelve, which are handy for the Movies Under the Stars that we saw one night while sitting in deck chairs by the pools (it was chilly, but we didn't mind, fortified as we were with brandy and and Irish coffee).
I am not sure when room service is free and when it isn't; you might want to ask if it matters to you. My wonderful husband went to the buffet every morning and fetched me coffee, without which I do not face the day. He could also have brought more food to our cabin, as some people did.
The final night, they had a Baked Alaska dessert procession after dinner in the dining room, but the dessert was not listed on the menu and I was the only one who ordered it. It wasn't my favorite dessert, but it was fun, and I can't think why they didn't put it on the menu.
The coffee is tasty but very low octane - apparently you can purchase coffee cards for fancy coffee drinks that my table mate told me could be used on any Princess ship - she saved hers from trip to trip. She said that they didn't bother to punch her card when she asked for plain brewed coffee at the coffee bars (I don't know where those were located), but that she got real coffee there. I found this annoying, but my evening Irish coffees didn't keep me awake, so there's the upside.
If you habitually drink wine with dinner, order a bottle and they will pour from it until it is gone - much less expensive that way, and no bother for them. I don't know how this works if you aren't signed up for one of the dining rooms, but I bet it could be arranged so they could find your bottle when you needed it if you were eating elsewhere.
I never did figure out what the much-vaunted Sanctuary on the upper deck was about - the only time I ever saw anyone in it was when we were seeing the glaciers in Glacier Bay and some people sought to avoid the wind (the area was opened up for this). I suppose if there are a lot of children on the ship, this is a place outside where you can get away from them, but they do charge for it, apparently, when it it open for business, which it never appeared to be on our trip.
We like quiet music, and were much impressed with the pianist and the string quartet who played various venues throughout the cruise - look them up in the ship's newsletter, the Princess Patter, an apparently un-proofread sheet that appears in your cabin mailbox each night. They don't keep extra copies, and had to make photocopies when I requested another copy of it so both my husband and I could refer to it, so don't lose yours.
For shore excursions, we enjoyed the railroad to White Pass (the shorter ride) in Skagway, the rain forest and wildlife tour in Ketchikan (bears!), and the butterfly garden and Butchart Gardens in Victoria. We were incredibly lucky to have good weather for each of these. We just walked around Juneau, having been there before. We found that many people were worried about missing their early tours, so they lined up 45 minutes beforehand the doors opened on the disembarcation deck and clogged up the hallways, which did absolutely no good at all, and some got quite distressed about those of us who appeared when we had been told to appear and were absorbed into the lines from the stairways and elevators. When there really was an issue regarding an early tour, the ship administration made an announcement asking those signed up for that tour to go to a particular area for disembarcation, and the rest of us waited until they were off; otherwise, there was no cause for concern and those who formed lines early just got tired and resentful after standing there for no reason. Disembarcation, once it began, was always quick, with at least two lines - just have your ship's card and a photo ID with you. Perhaps, if you are on a tour not booked through Princess, there may be a problem, but I suggest checking with the pursers to see what to do in that case. We weren't thrilled with the pursers otherwise, but our dealings with them had to do with the noise problem I describe below, and they probably knew that they couldn't solve it for us and just hoped we would somehow forget about it or take it philosophically. Every other staff member was competent, pleasant, and obliging.
One very large caveat: if you need to sleep before 11:45, DO NOT get a cabin near ours (D317). Our cabin was directly above the Wheelhouse Bar, which closed at 11:45 every night, and unless you can manage to stay awake until then, you may have problems. We had originally asked for a different cabin, but when I went online to check our status I found we had been "upgraded" and when I asked my travel agent (who had not been aware of the upgrade), she just said, "Oh. You've been upgraded." I asked if we had received an outside room and she confirmed that it was the same sort of room as we had originally booked, but didn't explain further. I now know why.
After the first night, I requested a room change, but was told that they were fully booked, that they would check with a supervisor to see if the sound could be turned down, and they gave me some earplugs (which did nothing to reduce the vibration from the amplified bass or to reduce the sound we could hear through our pillows, minus the melody or the lyrics - just the irregular noise). They told me to call them the next time the sound bothered us and they would send someone up to listen to it. The next night they had a different band, which was not quite as hard on us, and the next night we just stayed up until 11:45. One night my husband went to see another movie, while I stayed in the room and it was still pretty loud, but not as bad as the first night.
Finally, my husband and I were both in our cabin one night and the noise below drowned out the dialogue in the television movie we were watching unless we turned up the volume to the point of it hurting our ears, so we called the purser's desk and were told that they would look into it. Half an hour later we called again and they sent someone up, who agreed that the noise was bad (she said she didn't even need to come into our cabin because the noise was so loud in the hallway) and said that she would ask a supervisor to call us. Half an hour later no one had called us, so my husband called and told them that this was unacceptable; he was told that they were logging our complaint, and when my husband asked what good that would do us, they said that the cruise director would contact us the next day. We heard nothing at all the next day, but eventually (maybe that night, or the next? I don't recall), we found a message on our phone asking us to call and speak to one of two people, so we did, and neither was available but we were told they would call us right back. Nothing for half an hour; then we left. When we got back, there was a message saying that they would like us to accept $150 per person off of our shipboard account, and to call and let them know if we would accept this. We left a message saying that we accepted this, and got a return call to confirm our acceptance. They did give us $300 off our total bill ($15 each per noisy night, which I would gladly have foregone for the sake of a full night's sleep, especially when we had to get up early for a tour the next day).
Bottom line: It is unlikely that they can or will do anything once you are on board in a noisy cabin if the ship is full. It will not be a problem if you can stay up to the end of the music (11:45 on our trip). Otherwise, the cabin was fine, and the hallway was quiet. Since the noise ends before midnight, it's possible to make the best of it, but I would encourage you to complain pointedly if you find the noise to be overly loud before that time, as we did. Be persistent; this is not something you should have to tolerate, and they know it. The word "unacceptable" seemed to do the trick (husband is a retired merchant mariner and can speak forcefully). They were somewhat underhanded, I believe, in changing us from the cabin we originally requested without asking us, knowing full well what the problem was with our new cabin. We have since been warned by more seasoned travelers to instruct our travel agents not to accept upgrades, which may indeed be downgrades.
Do see if you can get a cabin as far from above the dance floor as possible when you check the deck plan (my husband visited the deck below the Wheelhouse Lounge and didn't think it was loud down there at all), and require them to recompense you if you get stuck and you find the noise objectionable. The cabin noise was the one and only problem worth mentioning on the whole cruise, and I am hoping they will take steps to solve this problem.