I apologise for commenting a bit late on this topic. The last coronation in Sweden was for Oscar II in 1873. Since then there have been no coronations. In 1907 the new King, Gustav V, declared a coronation would be inappropriate since it was seen to be out of step with the times. People no longer believed that God was involved in the making of Kings and Queens, there was a lot of poverty in the country and a general feeling that the monarchy needed to modernise. I suspect the new King was anxious to secure it for the future and put a more humane face on it.
King Charles is already King. A coronation, in my opinion, is just theatre. But, of course we will all get an extra Bank Holiday so that settles the matter!