I have another comment - my opinion, of course, especially without knowing your interests. Have you been to Copenhagen before? If not,
I find Copenhagen and the surrounding area to have many more options than Bergen and Oslo. I wonder if you are shorting yourself with the time in Copenhagen - especially as you will likely be jet-lagged on arrival. On the off chance that you haven't completed your research on Copenhagen and easy day trips, take a look at Helsingor, Roskilde, Fredricksborg Castle - all within an hour by public transit from central Copenhagen with multiple sites in Helsingor and Roskilde. 90 minutes one way, there's Odense - birthplace of Hans Christian Andersen and charming city center. Central Copenhagen has castles, palaces, museums, Nyhavn, Stroget street, churches, on and on.
If it was me, and it is certainly not, I would take one day from Bergen and one from Oslo and add to Copenhagen - probably at the beginning of the trip to recover. Just a thought!
I don't know Sweden at all, so can't comment, but I have had multiple trips to Copenhagen (and still am missing some sites I'd like to see) and I just completed multiple days in Oslo, Oslo to Bergen train, multiple days in Bergen.
Enjoy the planning!