We went to Copenhagen and Stockholm in June 2024 - we spent five nights in Copenhagen and 4 nights in Stockholm. We are in our 40s with no kids. We took the train to Stockholm from Copenhagen - it was not a direct train as we had to connect in Lund.
In Copenhagen, we enjoyed our morning bike tour with Bike Mike - it is a mostly flat ride with quite a few stops and a great way to see the city, especially one that has a huge bike culture. Also, would recommend a boat tour (we did one with Hey Captain!), Christiansborg Palace, taking a day trip to go to Fredericksborg Castle (easy train ride from Copenhagen), and the Museum of Danish Resistance (I know you said you aren't big museum people, but this one is done so well).
As for restaurants and bars in Copenhagen, we really enjoyed Warpigs, Lidkoeb (cocktail bar), Ruby (cocktail bar), Restaurant Barr, Baest (great pizza; definitely make reservations - we saw people get turned away), and if you want a total splurge dining experience, The Alchemist is incredibly memorable and a delight.
In Stockholm, highly recommend doing the tour of City Hall, visit the Royal Palace, Vasa Museum (it's not an overwhelming museum experience and really interesting), and a walking tour of Gamla Stan (booked through stockholmfreetour.com). We also did a boat cruise with Stromma one afternoon. We went to Skansen after the Vasa Museum since they are close to each other, but personally it was not our jam.
As for food and drinks, we liked A Bar Called Gemma (recommend reservations - we saw people get turned away), Lucy's Flower Shop (great cocktails), Omnipollus Hatt (casual restaurant with great pizza), Portal (one of my favorite meals of our trip), and Beirut Cafe.
Have fun planning!