We picked for the Baltic ports and because it was Oceania. The ports were extremely variable. Tallinn great. SPB, Gotenburg, Warnemunde, Oslo, very good. Crristiansand, Hamburg, Helsinki , Rouen, and Ghent so so.
Ypres rather than Bruges was a real treat for me.
Copenhagen is in a whole special class. Imagine the sheer stupidity of a huge cruise terminal and container port with a single 2 lane road as the only way out. Traffic was a disaster. Shuttle service ditto
Difficult to get around
Booked with Ulko tours. They were very good. Guide was fantastic. However they pack too much in.