OK, I am not big on Icelandic/Norse/Anglo-Saxon Mythology, by which I mean, I don' know much about it. However, is there a kind of underworld, as well as a Valhalla?
Thought: Perma death is a harsh, but intrinsic part of the game. Many of the negative effects may well be ameliorated by the future introduction of ancestor worship. But, what about making death and dying more interesting for those to whom it occurs?
Proposal: After death, the player character enters the world of shades. Everything goes largely monochrome, blurry? Other player characters cannot see you, but you can see them.
As a shade, you can choose to head back to the Circle of Brodgar, where a bright pillar of flame is visible (invisible to normal players, obviously). Throwing oneself into the flame means character deletion, such that you cannot log on your shade any longer.
A shade can interact with the world to a limited extent. For example, picking up objects and such. Each time they do so they use up a little of their energy, which recovers slowly over time.
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Now, that's all I have to say in specifics, but I would be interested to see what kind of ideas the devs could then work into this basic set up. It could be a platform for all kinds of cool mechanics. Especially, it could be worked into future magic/worship stuff.