Interesting flavors, several tweaks recommended
This is quite a good soup. Caraway is an infrequently used, but very good spice addition. What can make this more of a hearty soup is to add some potatoes and/or corn. That doesn't add a lot of calories, but it does make it more filling. Also, I found that salmon was kind of a powerful tasting fish, so I did some salmon and some other white fish like catfish or halibut, so the salmon did not overpower the flavors.
Pros: light, caraway is great spice
Cons: needed sprucing to make it more robust