I'll describe part of what I did in Norway last year:
I took the Norway-in-a-Nutshell trip from Oslo to Bergen (train, narrow-gauge train, fjord ferry, bus, train) with two nights in the very touristy but magnificently situation town of Flam. NiN can be completed in one (long) day with no overnight stop. There's a lot of great scenery on this trip, but it cuts across southern Norway; it's not coastal scenery. Honestly, I wouldn't make a first trip to Norway and skip the NiN route unless for financial reasons.
After a few days in the city of Bergen (pop 272,000; beautiful, but the area around the harbor is touristy), I took an overnight trip to Alesund (pop. 46,000) on Hurtigruten. The ship stops in Alesund (Art Nouveau town) about 10 AM and then makes a detour into the beautiful Geirangerfjord, returning to Alesund about 8 PM. I stayed on the ship until the return to Alesund; some would opt to hop off in the morning and take some sort of land-based bus/boat tour. I don't know whether that would be cheaper. Then I spent the night in Alesund so I'd have time to enjoy the architecture and see the Art Nouveau Museum the next day. I didn't run into many other tourists in Alesund.
Twenty-four hours later, I hopped on another Hurtigruten ship for the overnight run up to Trondheim. We docked around 10 AM. I spent several nights in Trondheim (pop. 182,000), partly to take a side trip inland to Roros. Trondheim is a stop on large cruise ships, I assume, but I didn't encounter throngs of other foreign tourists there. I may have been lucky in my timing, but Norway is very expensive. Perhaps for that reason, the tourist load is nothing like what you'll find in places like Rome, London, Paris and Venice.
Here's Hurtigruten's webpage for short excursions: https://www.hurtigruten.com/port-to-port/#/. You are not limited to the options shown there; single overnights are possible as long as space is available. At one time, point-to-point prices were lower on the Norwegian website. Right-click for the Translate to English option.
The Hurtigruten schedule can be seen at: https://www.hurtigruten.com/coastal-practical-information/sailing-plan. Use the pull-down box to select the summer schedule. As you can see, the stops are very short. If you stay on the same ship, you really don't have time to get off and walk around the southern ports except in Trondheim (rather briefly) and Alesund--and the time in Alesund is available only if you don't stay on the ship for the trip into the Geirangerfjord.
As of last year Hurtigruten ships ran five days a week. There's now a second company running the coastal route, Havila. Perhaps between the two of them there's a departure every day. I believe someone reported here that the Havila ships are newer. I was completely happy with the two Hurtigruten ships I used for my brief trips, but they do vary.