Heaven and Hell Noir world for DND

(This is my first world inspired by real DND lore, many names and Ideas are from that, but this is still my own unique Idea)

In the beginning, there was Good and Evil, and Good fought the Evil. Then Good became organized and out of the Arborea came Mount Celestia. Mount Celestia became the Hierarchy of Angels and Archangels, as well as the domain of Lawful Good individuals. One of the Archangels, Asmodeus, proposed a harsher, crueler way of fighting the Demons and the Abyss. Mount Celestia accepted his proposal, but he was deemed evil, and the Nine Hells were created, amongst other things, as a prison for the Demons. Eventually, Lawful Heaven and Hell discovered a way to defeat the forces of the Abyss, but it involved locking off all of the Chaotic realms, Good and Evil alike. Both Heaven and hell found themselves more aligned with their lawful calling than their prospective good and evil callings, and so they locked away all of Chaos and created the Spire.

Hallowspire is the common name for what is currently included in all of creation, a great city stretching from the Seven Heavens down through the Nine Hells. The mortal layer is the city of Gloam a city of angels, devils, and mortals.

The Spire has found itself in a compromise that has left the various factions vying for more power. The denizens of the nine hells have found themselves incredibly rich, the use of demons as slave labor, combined with the selling of natural resources to the mortal world and Heavens, has made a booming economy for the devils. However, in Hell, they are under a strict hierarchy with little social mobility, and most joy is outsourced from Mount Celestia.
The mortal plane is currently profiting the most; they are in control of the trade between Heaven and Hell, and at the same time, they have the most freedoms of the three planes. However, only mortals can exist on this plane for an extended period of time; all mortals eventually die and drift up or down.
Heaven is facing problems of its own, as it only has access to paid labor and have found themselves in an economically weak position. Due to the easy life in the mortal plane, many souls find their way into Heaven, but fewer and fewer are climbing Mount Celestia to join with the essence of the plane. As such, this plane is experiencing overcluttering.

Tieflings and some Minor devils and other crimebosses near or on the mortal plane are searching for ways to stay on the mortal plane longer or even eternally. They have found allies in some angels as they believe their experiences with angel essence may find a way to allow demons to exist in Mount Celestia, thereby allowing an unpaid workforce.

Players will, after the first session, find themselves scapegoats in this plot, blamed for the murder of an angel.
Warlock player will find out their "Great Old One" Patron is actually just one of or a combination of the Chaotic Gods. Maybe they can bring the chaos back.

If I may ask for help, I'm struggling to think of what makes the Angels and denizens of Heaven exist in more of a struggling situation. Why would they turn on other Angels? What are they really looking for? Something helpful is that inorder to keep law, the powers that be have condensed all the matter in the universe so that not only the mortal world, but also heaven and hell exist within real matter, allowing goods to be traded throughout.