The concept of Hades and the realms therein evolved according to the texts that survived. There was probably never a "Hellenic Unified Theory" of the underworld and the location of its realms. Different authors give us different accounts in different eras. But as a general guideline, it's important to consider that the Greeks would have had a different understanding (or even absence) of some of the concepts in/underlying your question than we do today. For example:
Soul
The concept is different from the Judeo-Christian definition. A psyche (Ancient Greek: ψυχή psykhḗ, of ψύχειν psýkhein, "to breathe") comprises the mental abilities of a living being: reason, character, feeling, consciousness, qualia, memory, perception, thinking, etc. Psyche was also the name of a deity.
Greek philosophers, such as Socrates, Plato, and Aristotle, understood that the soul (ψυχή psūchê) must have a logical faculty, the exercise of which was the most divine of human actions. At his defense trial, Socrates even summarized his teachings as nothing other than an exhortation for his fellow Athenians to excel in matters of the psyche since all bodily goods are dependent on such excellence.
Hell
Early New Testament authors chose the word Hades to translate the Jewish concept of [sheol][1] and the Christian concept of hell. To the Greeks, Hades was however a very different concept. As mentioned, the quality of afterlife was much more dependent on remembrance than on actions in life. The notion of judgement and punishment by hell as in Christianity is mostly absent.
Afterlife
The Greeks originally had a very different idea of the afterlife than in Judeo-Christian or Egyptian mythology. In ancient Greece the continued existence of the dead depended on their constant remembrance by the living. In ancient Greece death was defeated, not by the gods, but by the human agency of memory.
Afterlife & Underworld were evolving ideas in Greek mythology
The after-life for the ancient Greeks originally equated Hades, a mostly grey and dreary world. In Homer's Odyssey in which Odysseus meets the spirit of the great warrior Achilles in the nether-world where Achilles tells him he would rather be a landless slave on earth than a king in the underworld.
By the time of Plato, however (4th century BCE) the after-life had changed in character so that souls were better rewarded for their pains once they had left the earth; but only in so much as the living kept their memory alive. So different eras in Hellenic history (and the development of the mythology) would render different conceptions of the underworld.
While both Elysium and Tartarus existed in the time of the writer Hesiod (contemporary of Homer) they were not understood then in the same way they came to be.
Eusebia
It was considered one's duty to the dead to remember them well, regardless of the life they had lived, the mistakes they had made, and, thereby, provide them with continued existence in Elysium. This remembrance was not considered a matter of personal choice but, rather, an important part of what the Greeks knew as Eusebia. We translate the Greek word Eusebia today as `piety' (again by Judeo-Christian influence) but it was much more than that: it was one's duty to oneself, others and the gods which kept society on track and made clear one's place in the community.
[1]: https://en.wikipedia.org/wiki/Sheol#:~:text=Sheol%20(%2F%CB%88%CA%83i%CB%90o%CA%8A,also%20called%20Hades%20in%20Greek.
