Hi t-$
I also live in Norway (Trondheim) and have done several hut to hut ski tours in the past easter periods, and some smaller ones outside of this.
The main trips I did were several in the Sylan massif near the Swedish border (I did up to 5 nights but longer trips are possible) and one three night trip in the Trollheimen massif, what is called the "Trollheimen Trekanten". The Trollheimen trip had quite a bit more topography and was overall more spectacular, however the Sylan area is also very nice.
Regarding Sylan -
We did on one trip use cross the border into Sweden but the Swedish touring agency STF has a different, much more massive approach to mountaineering and in some Swedish cabins eg. Sylarna Fjällstasjon there were >150 people staying, which we did NOT like. The Norwegian cabins were much cozier. So far my favorite trip there was:
- Drive in to Bjørneggen DNT cabin (self service, we did not stay there as it is not a nice cabin)
- Ski to Schulzhytta (full board), then to Ramsjøhytta (self service), then to Storerikvollen (full board, highlight in terms of cozyness), then back to Bjørneggen. 3 nights, 4 days, 18-25 km / day.
With public transport the possibilities have to be checked, there are buses to some trailheads but I have not used this option so I am not sure.
Re-Trollheimen:
https://www.tt.no/trekanten-vinter/
In Trollheimen, the best way to go with public transport is probably to fly to Trondheim (Oslo is further) and then take the train to Oppdal. From there find your way to Gjevilvasshytta (bus? + ski), then ski over to Jøldalshytta, Trollheimshytta and back to Gjevilvasshytta. Then ski + bus back to Oppdal.
Here is some other users website with some pictures so you get an idea
http://folk.ntnu.no/strimbec/Personal/T ... eimen1.htm
If you like steep, it is possible to summit the Snota mountain with BCD skis from Trollheimshytta.
Other tours we have not done include Hardangervidda (many DNT cabins there!), Rondane (not much snow usually).
Hardangervidda is accessed from, for example, Finse wich I think can be reached by Train from Bergen.
The DNT cabins are spaced out about 15-25 km between them, this makes a reasonable distance.
Accomodation - It is worth getting DNT membership if you sleep in 3 cabins per year or more.
Around Easter many of the main DNT huts have a warden there which means that you are not allowed to cook in the huts yourself. Accomodation costs 860 NOK (=86 euros) for full board for DNT members, including dinner, accommodation, breakfast and pack lunch. To me living in Norway, this is pretty good value. Cabins which have wardens should be booked! But no cabins have wardens year round. Next year for example, Trollheimshytta has wardens from 3 April. Before that, you will have "self service" meaning that you take care of yourself, and pay less.
It is not possible to use the kitchen when there is a warden, this means that in the high season, you pay full board or go to another cabin.
If you are a DNT member, you can obtain a key for all the "self service" cabins. These cost less at 390 NOK/night (39 euros), and you can get preserved food from the supply (self service) for which you have to pay what you use.
In some of the flatter topography tours - e.g. Sylan and Hardangervidda, some people pull ski sleds with tents and camping equipment. However be aware that temperatures around easter can be down to below -20 centigrade (or colder, but that is the coldest tour I had in Sylan), and we had hurricane force winds (180 km/h) in the mountains a few years back at easter in Trollheimen, which made us abort that trip.
A ski sled is not manageable in the steeper terrain of, for example, Trollheimen.
Camping in a winter hurricane is potentially fatal.
How many days did you want to ski for?