Scandinavia trip itinerary

That seems like a lot of changes in lodgings...

It is a long trip. Do you have advice on what to cut or where to stay longer?

My memory is a little hazy because some of what you are doing was my last travel before Covid. But I did combine Norway, Finland and Copenhagen that trip and I did use Hurtigruten, which I had never heard of and loved. How old is your baby?
Travel is intensely personal. I decided to not include Sweden nor Tallin, but also wanted almost a week in far northern Finland and had about 3 weeks. I flew into Oslo from the US, and was fortunate to have a former exchange student's family host me for two days. The Viking Museum was wonderful, and the KonTiki etc. The stave church there was the only one I saw. That complex of museums was a little way outside the city, they drove me- ditto for the ski museum, also wonderful. I am trying to imagine this with a small baby, though and public transport.
I then used the Norway in a Nutshell route to get to Bergen for the Hurtigruten ship and perhaps it's this part where you could do some rearranging and/or eliminate overnights to save time and hassle. There was not much in Flam, it is tiny. I took the "express" boat from there to Bergen but it was NOT express. And I think not nearly as scenic (at least in summer, I also was there in late July/early August so not much snow) as where you will have been? I also think you could have less time in Bergen. The English tour RS recommends was fabulous for the historic core area, but in one really long day I saw everything on my list and more.
The ship might be an easier way to see scenery, especially with the baby? Stay on it longer and eliminate some other places on your list. I went all the way to the terminus at the Russian border (many people flew back from there to wherever they were going). I also did some of the offered shore tours which I loved (easy walking), albeit expensive. With all the hotels and transport I just wonder if longer on the ship might work for you, too and be comparable in cost for a shared cabin? Mine was very noisy, in the middle of the night when cargo was loaded or when it was stopping/restarting. But I just loved it and the food was amazing.
Anyway, I also had 2 days in both Helsinki and Copenhagen after the week in the far north.
If there are specifics you really want to see, that would be helpful. Frankly, even without a baby this seems like a LOT?
Best wishes! and how incredible to be able to travel with your father!

I agree that this seems like an exhausting trip with way too many short stays. It's possible you can't avoid having two separate stays in Copenhagen; I haven't researched transportation to Aero. I think the Norwegian routing can be improved. I'd try for something like this:

Oslo - Nutshell - Bergen - Hurtigruten to Alesund - Alesund - Hurtigruten to somewhere in the Lofotens and local transportation in that area - fly from Bodo or other northern airport to next stop (possibly with connection in Oslo). Alternatively, you could start as you have planned but take the Hurtigruten ship from the Lofotens down to Alesund, stay a night and then continue on to Bergen-Nutshell-Oslo.

Have you really dug into the schedules for the transportation you will need? Not all the links run as frequently as one might assume. As far as I know, Hurtigtruten is now running ships about five days a week, not daily--though there is a second company with a similar route that might fill in the gaps.

Balestrand is a particular challenge. The express boat only goes to Flam once a day, departing Flam at 1530 and reaching Balestrand at 1650. The return trip departs Balestrand at 1155 and gets to Flam at 1340. So one night in Balestrand gets you little time there--basically just the evening you arrive and a few hours the next morning if you are early risers. Norway has a lot of overcast and rainy days. You run the risk of having no good weather in Balestrand (and Flam) when you plan such a short stay. Starting the day in Balestrand will mean a long travel day as you complete all the Nutshell segments on the way to Bergen. I believe Rick recommends staying in Balestrand only if you can spend at least two nights there, and I decided not to do even that since I wasn't planning to rent a car. The public buses serving the fjord area are very infrequent, so you need to plan any sidetrips very carefully before deciding where to stay. Flam is not particularly charming, but it makes a lot more sense from a logistical standpoint.

You didn't mention any budget concerns, so it may not be an issue for you that Norway is very expensive. However, you may run into difficulties finding lodging in the rural areas (Flam, Balestrand, Lofotens). Perhaps things will be loosening up in September.

The Lofoten Islands are absolutely gorgeous! But without a car it will be difficult to see anything off the main bus route. It seems like you will spend as much time on flights and the ferry boats traveling to and from as you’ll have there. Even with a car 2 days will not be enough time to really explore the area. You could add some time by flying in and out of Svolvaer or arriving via Hurtigruten and renting a car to maximize your short time there. Otherwise you may want to save it for another trip and use those days to expand other parts of your trip.

We did a wonderful cruise out of Copenhagen that visited 6 Norwegian ports (on the North Sea) all the way to the North Cape.
The fjords were awesome.
I am so glad we did a cruise instead of all that ground traveling and changing hotels.

Before the cruise we did do a couple of days in Stockholm and wish we had do more there.