just read the shoki, the real one, the good translation of the actual original (insofar as any of these texts have a good actual original)
some comments
the lack of an actual (world) creation myth is hella cool. You really get the sense that it's a local history and that the separation of heaven and earth was something happening in the background because of whatever celestial politics above the characters heads. Like, there's reference to a celestial hierachy that the founding characters are already several generations down on but everything that actually happens clearly concerns japan. The ongoing separation of heaven and earth is happening in real time and the distance is made reference to, but the actual cause of the seperation is never mentioned at all.
oni are actually female
the shikome (aka hisame) are in the original and in the alt. ver. they're the eight thunders (i.e. the oni) and it's clear that they're the same characters (the etymology of hisame is even similar, being ~storm)
particularly with the shikome/hisame clearly being identified as the primitive boogeymen in the same sense as the 'cover your navel when there's thunder' sense of oni as boogeymen, they're clearly the same thing (and very explictly female)
I'm amazed at the degree to which amaterasu is actually the authority and active ruler of the local heavenly realm (i.e. absolutely). Considering that all the pre-japanese-literature historical documents from the mainland talk about the ruler of the unified island as an empress it really seems like himiko etc. probably were real or at least considered to be real by all the chinese and later japanese (which is the same as being real).
Given the chinese history of sort of offshoot female rulers in the local environs (pirate queens etc.), this isn't really that surprising. It's still pretty interesting, especially since it's clear that it's a theocratic monarchy.
Izanami likewise doesn't flinch a fucking step. Izanagi literally shits himself and runs away and she equitably accepts the divorce, there's never an actual contention where they compete (in the line where he seals the entrance to stymie the shikome/oni, izanami has already been to where he is and left a message with the guard). Everyone else dies when they die and izanagi retires to be a minor shrine diety in his daughter's court but izanami continues to be on the offensive in their relationship and doesn't seem to give a fuck about having died at all. It's actually kind of shocking that characters who die are actually dead in an ancient mythology but she's the only exception.
Yomi is consistently characterized as a series of winding roads. Other than associations with a low place and distance from heaven, there's little to suggest that it's the underground/hell/gehenna-like place it's usually depicted as in modern fantasy or from the indians (or their descendants). If I was to be generous and assume that it is a cavern, the idea of a huge number of long and winding roads (and entrances clearly on the surface) suggest that it's more like a mass of long and winding "roads" as in tunnels in a cave system.
Given the only other inhabitants are found serving izanami after she's been there for like three days, it rather feels like her choosing to stay there when he retreats to heaven is paralleling amaterasu ruling over the local heaven in a sort of mirror now below to the above the land of reeds (=earthly japan).
There are a shit-ton of native gods and no really clear indication of where they came from. Are they the children of the islands? Were they already there? How? The islands are creating in the text, so clearly the native population have to spring up in this timeframe as well. An account is given of how domestic crops and some domestic animals came to be (and others are clearly imported) but insects (which are also identified with some of the untamed native gods that the celestials subjagate) were obviously already there, and the celestial gods are assisting their petitioners in resisting them.
The actual mythological section before the leviticus style mythologised history begins is pretty damn short, though the shoki was compiled as a historical document foremost. The myths are presented as transcribed-as-best-as-possible local tellings.