I've finally got the itinerary set (mostly) for my week in Scandinavia, with a couple of nights each in Copenhagen, Oslo and Stockholm. Of course, nobody would want to spend so little time in each city ("If this is Tuesday, it must be Oslo"), but it's the best I can manage.
The overnight ferry from Copenhagen to Oslo will save some daylight for the city. Can you ask for a starboard (landward) cabin when you board the boat?
Thank you to all who posted their ideas!
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Middle_Seat