Copenhagen & Norway/Sweden Itinerary

I'm traveling to Copenhagen in early-September for 3-4 days. We have 9 days afterwards to either go to Norway or Sweden, or both. Definitely understand 9 days isn't enough but just trying to see if it this were possible:

1. Overnight ferry from Copenhagen to Oslo
2. Stay in Oslo for 1 night
3. Do Norway in a Nutshell split over 2 days (not sure which stop to stay at though) to end up in Bergen

4. Stay in Bergen for 3 days

5. Fly to Stockholm for the remaining 4 days.

We enjoy nature and city life (architecture and museums specifically) so we're pretty balanced. However, we are traveling with older folks in their 70s so we can't do any strenuous hikes. Any thoughts are appreciated