For Stavanger and Bergen you can easily walk around the towns and in the case of the latter take the funicular up the local mountain. One also docks right in the middle of Alesund but there is more limited sights there. Geirganger/Hellesyly one needs to consider an organised trip as there is little obvious alternative. At Flaam one can book the local train oneself and go to Myrdal and back within a couple of hours and this is good.
At Flaam we tried to get a ticket at the bottom, but was all sold out. So we deceided to walk up the valley. As we were walking we noticed that there were spaces on the train. So we walked to the next station, got on, tried to pay the ticket master, but he was so busy. In the end we had a free ride!!! all the way up and back down again.