Hi Jon Olav! Nice work. There are a few other aspects you could integrate in your station-to-station viz. The first is distance of trip, that will give an impression of the distribution of how far people travel. These could be colored on a gradient.
The more interesting one is direction from-to center or skirting around the city. Like most small-ish cities, Oslo has a clearly defined center and a lot of travel will be towards and away from those central areas (Grønlad, Jernbanetorget, Karl Johan) to the more residential ring surrounding it (Sagene, Kampen, Frogner.) This “star” pattern is evident in transit maps, for instance.
Choosing different colors for inwards or outwards motion would probably reveal patterns related to morning and afternoon rush.