Scandinavia is dark almost all winter, and sunny all summer.. I am from Canada orignanlly
No its not. Kiruna is just a super tiny ass place thats a 10 hour drive up north from civilization, and it starts to thin out a couple of hours before that..
If I were to go here in the summer, I'd hit up the capitals first of all. Hit up Oslo and shit real quick but I wouldnt stay too long, its so expensive there its fucking regular. Even compared to Sweden, Finland and Denmark. Then hit up Swedens west coast in the south for some beaches and chillin, then head over to Stockholm on the eastern side too.
From there you can take a cruise over to Helsinki for relatively cheap. Spend the night on a big boat, gamble a little and eat good food. You can take the car on there with you for an extra fee too if you drive around in a rented one.
Then after that just go back another day with another boat and drive down to Denmark. None of these countries are wide so driving between them doesnt take too long. Denmark are just all around mellow as fuck and not that big so you cant really go wrong driving around there.