Somewhat whimsical, yet somewhat grappling with dark undertones, possibly due to the trauma of the war.
The moomins starts with a great flood that washes them all away to live in a new place (I think this is a parallel to the Finns moving out of Karelia after the war. I believe this was the largest migration of people that had occured at the time, and it has been described as causing generational trauma to the Finnish).
In addition I believe MoominPappa deals with issues of depression or something?
Fantastic creatures diving to retrieve their pantry supplies or the head of a family grappling with a mild midlife crisis is not exactly on the same scale with a band of warriors reclaiming their homeland and in passing dealing with the eternal evil.