We just got back from our Northern Europe 7 day
DCL cruise. My recommendations would be to do private tours if you can. Our experiences (family of 8, ages 9 to 72):
Tallin - private tour "Food Sightseeing Estonia" We had a walking tour of Tallinn, stopping for a multi-course meal in various locations. Beer/soda and appetizers at the top of one of the old towers, marzipan at the store that invented it, drinks at a wine cellar (which the highlight really was the story of the founder and his experiences before/during/after the Soviet occupation), soup in a Medieval cellar, lunch and dessert at an old tradehouse/grainery. Our guide was fabulous and the food was great. 90 Euro/person, including transfers to/from the pier. (It is walkable, but my parents both have bad knees.)
SPB - private tour with TJ Travel. We contacted several agencies and went with the one that was willing to modify the itinerary for our multigenerational group. We had a large van, driver, and guide. Itinerary as follows, cut and pasted from my email:
8.30-9:00am meeting your guide near your ship
9-10.15amCity tour: City tour includes driving and photo stops in the most beautiful, historical places in St Petersburg. Your guide will tell you different stories and legends about famous palaces and architectural ensembles. You will see: Nevsky prospect (the main street in St Petersburg), National Library, Kazan Cathedral, the Square of Arts, Russian Museum, Ethnographical Museum, Michael’s Castle, Summer Gardens of Peter the Great, the log cabin of Peter the Great, Aurora Battleship, the Spit of Basil Island, The State St Petersburg University, the Monument of Peter the Great, Admiralty, Theatre Square with famous Mariinsky Theatre, St Nicholas Cathedral, Church on the Spilled Blood (photostop) (I'm not sure we actually saw all those things, which is fine by me.)
10.15 am - 12.15 pm - Inside guided tour of the Hermitage( early entrance) + we can add a visit to the Knight's Room (if you have boys in your group, it will be very interesting for them )
12.30 pm - 13.30 pm - lunch (optional) (at a restaurant where you will have a chance to try Russian blini and caviar) we went to Tepemok, a Russian "McDonalds", super cheap, fun fast food for us to try.
1.30 - 2.30 pm - tour at the Cat Museum
2.45-3.15 tour of the Church on Spilt Blood (we went inside, which was amazing, many tours just stop and look from outside.)
3.30-4.00 hydfrofoil to Peterhof
4.00-5.30 pm guided tour of Peterhof gardens
6.30 pm - 7.30 pm - Stroll along Nevsky Prospect, stop for coffee and ice-cream
Our guide then got us checked into a restaurant for dinner. We ate a Teplo, a great home cooking sort of trendy place. We had a wonderful meal. The food was great and our server was a gem. We chose the restaurant from a list of recommendations from the agency and they made reservations for us. The driver sat outside the whole time, so was available as soon as we were done to bring us back to the ship. The visa issue was a non-issue and the guide met us at the door as we were leaving customs. The total price was 170 Euro/person, not including meals and tips.
Helsinki - Three of us did the DCL Reindeer tour. That was cool, just because I have a thing about reindeer. It involved driving an hour, walking about 30 minutes thru the woods, then getting to the reindeer. The local guide was an older lady with the driest personality I've ever seen, and a very monotonous voice. She was informative, if you could stay awake. Downside was we saw almost none of Helsinki. By the time we got back to the ship, going back into town would have been very tight time wise. The rest of our group did the DCL speed boat tour. From their stories, they had a great time in a "I hope I don't die, at least I have a big survival suit on" snot flying everywhere sort of way. The trip left early enough that going into Helsinki was not possible, and got back right before the ship pulled out. They also saw none of the city.
Stockholm - we all did the DCL Food Market, Old Town, and Vasa tour. We were all pretty unhappy with it. LOTS of sitting in traffic on a bus. We had less than 20 minutes at the market, and less than 30 minutes at the Vasa, before we had to be back at the ship for the next group to use the bus. The only saving grace is we got back to the ship with 4 hours left in port, so most of us went back into the old town on the free DCL shuttle.
We all decided the private tours were better. Traffic is not so much an issue because you're in a smaller car. You can change up the itinerary on the fly. You're not tied down to someone else's schedule. For what we paid, our private tour prices were comparable to DCL excursions that were shorter and had no flexibility. Stockholm, if your'e ok with walking a bit, would be easy to do on your own. All the main things to see are pretty close. Tallinn as well. For me, though, I really enjoyed the talking to the local guides. That adds another dimension to the trip, and gives me a better understanding of the country instead of just reading a walking guide.
We were lucky that we had enough in our group to get good rates on the tours, but you can get on your cruise meets and find others to do tours with you and drop the cost most likely.