IC "upon trembling wings" modern day einherjar collection
Good questions! I am always in need of good question askers :) although I am not a historian myself, and am like as not to weave a thread from what knowledge I have stored, I particularly welcome a focus on details and particulars, and in this sense always invite my players to collaborate with me. I see freeform as a way of investing with the story, and the extent of my gming dependant on how aligned my writers are with said story, does that make sense? But it's a two way street, my writers can often be more correct than me, or have ideas or questions I've never considered, and so I rely on them also to keep me, shall we say, focused? :)
I was trying to put up a semifactual narrative with quotes and such, but the long and short of it is that einherjar means "those who fight as one" or "those who fight alone". They are classically warriors who, upon death, are rewarded their bravery by being escorted to Valhalla- the hall of oden where he has gathered these warriors to await ragnarok- the end of the world, via calamitous occurrence and malevolent intent. Mainly giants and demons, the latter part being the main source of inspiration for antagonists, as well as key figures of the myth, fenrir, and the world snake, and some others, in addition to rebellious valkyrie and in many ways, human society itself, or rather, the way it has been warped till now.
As for the valkyrie, they are often depicted as winged warriors themselves, female, the lot of them, and they choose amongst the dead of battlefields and escort them to valhalla. They are sometimes described as also choosing the fate of battle, and of loving or having life for or with men(or women xD) and it is here I have taken license to paint them as muses, the import of which I shall attempt to convey in a second.
The reason for the desolate picture described in the op is that, although ragnarok has not yet descended, earth is a battlefield lost, in a sense, due to humans having, as a whole, managed to cut themselves off from myth entirely- owing due to this their advances in technology, and their strongholds within reason acting thus as a barrier to any "foolish stories".
There then, in a sense, lies a sort of half death, or metaphysical death, amongst these humans: here we see the valkyrie as muses, floating over the battlefield of mankind's war against itself, looking for those worthy. However, in this sense, to die on the battlefield nobly and in order to be chosen, one must be at least facing this general direction: that's this bit here "The comforts of society provide but a distraction, and deep within you lies a restless hunger, a deep seeming that has laid about you since birth."
You are correct in thinking towards superheros, and also in regarding restrictions/themes; in the mythology ragnarok seems to be in perpetual postponement, and in regards to the setting of the story the time has been chosen due to the fall of man's heart.
So the superhuman abilities are thematically connected to passions- typically virtues- and are described as such when the players become accustomed to them- rather than passions I should suppose more accurately to say identities, inner strength.
So the antagonists are twofold- there are the obvious, physical threats before mentioned-, and then the vague, underlying cause of calamity and disaster itself- this idea of a dark intent within reality itself set opposed to inspiration- itself a cosmic portrayal of the inner darkness of mankind.
As for the powers themselves, they will come later, the opening premise is coming to your own terms within this framework, for which I am here to be what guide, inspiration and or resource as I can manage to provide, as the character of your choosing.
Thoughts?