My spouse and I did a 14 night cruise from Dover to the Baltic on the Ryndam. We had a great time!
We chose this particular cruise primarily for the itinerary, which offered overnights in both St. Petersburg and in Stockholm, as well as stops in Copenhagen, Germany, Helsinki, Tallinn and Visby, a quaint village on Gotland. The 2 day Stockholm stop should, in my opinion, become the standard for all cruises in this region; it was our favorite port and there is so much to see and do that two days is barely enough; I would have felt cheated with just one. We also, frankly, found the airfare from our city in the US to London to be much more affordable than to Rotterdam/Amsterdam or Copenhagen. (Suggestion to HAL: make Dover the Ryndam's home port and cruise from there more frequently)
We had been on the Ryndam in 2009 for an Alaska cruise. We generally enjoy the smaller ships, so we found the slow pace of the Ryndam relaxing. We were very pleased by the updates to the ship since that time; the bathroom in our cabin had been completely remodeled (no more pink tile!) and we really liked the addition of "Mix," the new themed bar, where we were regulars at pub trivia. Yes, there is some minor shabbiness (public toilet seats that need to be replaced, trim in elevators that need new stain, areas where carpet could stand replacing) but hopefully that will be attended to at the next dry dock and it did nothing to lessen our enjoyment of the cruise. We had 2 minor repair issues in our room (electrical plug went out and the toilet would not flush one morning) which were attended to promptly.
Our service on the ship was generally excellent. Our room stewards were efficient and satisfied every request we made. The bar staff was prompt and helpful. Our waiter in the dining room not only gave good service, remembering our beverage preferences (even putting a bag of my favorite brand of tea down during the appetizer course one night because the dining room was running short and he wanted to be sure I had my choice) but actually gave us better advice about Russia and money exchange that the travel guide on board did.
Oddly, the only time the service on board lacked was at (1) the embarkation lunch in the dining room and (2) the "Mariner's" brunch. It was absolutely terrible both times. It seems that these are areas where HAL would want to shine. Since I think everyone who was at these events complained, they hopefully have gotten the message.
The cruise was very port intensive -- no time to get bored!
We booked all our shore excursion from HAL. Yes, they were expensive. The all-day escorted excursion into Berlin, which we did by bus instead of train (not available for our cruise, for some reason) was particularly expensive, but worth every dollar; in fact, it was out favorite excursion. Our guides were universally good (especially in Berlin, Stockholm, and Visby), the coaches comfortable, and we were never late returning to the boat. Interestingly, there was a representative of the Ryndam on every excursion. I don't know how that is decided, but we had everyone from the head of security to a dancer to a room service steward. If I did this cruise again, which I would do in a heartbeat, I might be comfortable going off on my own in any port except St. Petersburg. Hop-on Hop-off buses were readily available in Copenhagen, Tallinn and Stockholm, though I heard from other guests that Helsinki was a chore to get into. But for a first-time visit, peace of mind is worth the cost.
A word about St. Petersburg, as this is always deemed the "jewel in the crown" of the Baltic cruises. We never waited less than 30 minutes in passport control and had to go through it getting off the boat and returning to the boat each time. (Since we had shore excursions both days and a third the first night, this meant 6 trips!!). This seemed to be due to under-staffing. For example, when we returned at 10:00 from the Hermitage there was only one booth open. That said, our Russian guides on our shore excursions were all friendly, attentive, knowledgeable and helpful. A HAL shore excursion is a must in that port.