These lists of the nine worlds are modern speculations/generalisations. I would like to see elder literature or source material support this.
Don't forget that the bardic and scholarly tradition peculiar, somehow, to the Northern Islands (Orkneyar etc.) and Iceland, left Norway, and Scandinavia because of resistance against the novel feudalism of King Harald of the House of Ynglings, in alliance with the House of Wessex, King Athelstan, in England, and the Liudolfings, who will become known as the Imperial Ottonian dynasty. Snorre Sturlasson defend the particular intercultural syncretism of the Norse. He explains the relationships between the Norse scaldic tradition with that of Vergil's Aeneid, in particular, yet also the Iliad. He claim that Oðinn's son Viðarø is Aeneas. Of course Snorre is familiar with the Pythagorean practice of metempsychosis that Vergil teaches. Oðinn may thus be avatar of both King Priam, as he claim, and of Angxises, as well as King Memnon of Ethiopia, as he reckognizes the Prince Tror of Ethiopia as Þor, the guy with the hammer. Wonder why this attestations of Snorre is ridiculed and regarded vicarous?! At first I thought that Snorre's claim that Oðinn is (the avatar/metempsychosis of) King Priam, was conflicting with him identifying Viðareu with Aeneas of the Aeneid, the epic poem, because Aeneas' father is Angxises. Oðinn is father of Viðareu. Now I find it plausible that Snorre is very well aware of how Angxises and Aeneas is an intended mirroring of Priam and Hector, expressed in the Iliad: Poseidon, God of the Sea, while observes the fatal situation Aeneas is in (while fighting with Achilles, who next will slay Hector), urges the other gods that they should rescue Aeneas, "For", he says, "it is appointed to Aeneas to escape... thus shall mighty Aeneas, be born in the afterlife of his children's children, rule over the Trojans once again... the Romans. Vergil indicate, interestingly, that Aeneas was born again as Marcus Claudius Marcellus, who might have become the first emperor, had he not died of the pestilence that his uncle Octavian survived from, who became Emperor Augustus son of God.
Other stratas of the Norse Sagas, makes it even more evident that supernatural figures are figures of speech relating certain peoples and their manners. Youthunns and Elves and Goðs are like the Vanir and Asians, people who are practicing different kinds of avatarism. They are not either mundane or cosmic. What brings them all together, is the secret of Amphictyonia. In the Norse Skaldskaparmál, it is the Youþunn Ægir, aka King Lear, who fascilitates the symposium that brings peace, at least the Greet, between the Greek Achae, aka Danoii, who is the Vanii, and the Hittite Trojans, who is the Æsian. Prechalchedonian Christianity was pro-actively syncretistic. That changes dramatically with feudalism, and the totalitarian monopolisation of sanctified life, making the Benedictine Rule the only rule. This only comes about with the emergence of Charlemagne as Emperor. The Norse culture flourish, from the Black Sea to Iceland. The fall of Rome is about western Europe, not Eastern Europe. The Salian Franks, through their Merovingian anchestors, claim the true inheritors of the Roman Empire, at the moment the true Roman Empire in Constantinople is more and more ruled by empresses and evenuchs, caring more for philosophy and art than war, nourishing increasingly cordial relations with the golden era Khalifat centered on Bagdad, and the Jewish Khaganate of Khazaria. The too high status of women in Byzants is the reason why the Salian Empire emerges! It is very sad that it is the spread of this rather strange and perverted form of christianity most people tend to think is christianization; not that the Benedictine Rule was in any way constructed in order to become the instrument of oppression that it became. Snorre Sturlason is quite clear, the scholarly skalds of his lineage are not pagan, although he admits that peoples in remote places resort to pagan customs as they forget the bigger picture, how it all connects to the Greek and Semittic, as well as the to the shamans of the Hunic confederates.
Dwarves is to me a huge mystery. Our culturally dependent default notions of them must be wiped out. I think they, as much as Joþunns and Elves, presents a certain sphere of existance in the cyrcle of becomings conferring both the Hebrew concept of Gilgul, the metempsychosis of Pythagoras, or the Tibetan Srid pa'i 'khor lo. The etymology of dwarves has made me see them as protector spirits, possibly particularly related to oracular practices (as that of Delphi); more specifically I relate them to Time. The hours of the night are conceived of as Watchers, their etymology runs in that direction. Thus I see them as the biblical Egregors - ἐγρήγοροι (koine Greek), and Aírs - עִיר(Hebrew). That's why they are dark-elves. In the Norse corpus some Dwarves' names are reckognized in the names of mythological animals,like the harts Durethrough, Dwellinn, Duneaíreu and Dóinn and even items, like Draupnir. I find it significant.