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Maybe we may not see a religion where the concept of heaven and hell doesn’t exist, because all of the religions relied on a set of beliefs, faith, and customs brought in by our ancestors or due to the collision with other civilizations. Even if there is a place in the universe where life does exist, still I doubt whether we can find any such diverse life forms such as humans beings elsewhere, because of the diversity in character as well as nature. When we consider humans, we can see the most innocent human and also the most barbican human co-exists together, the poor co-exist with rich, and the strong co-exist with strong. That may not be the case in the arena of the universe.
As I have mentioned in most of my articles, in the universe the size and strength of an object do matter for its survival, the strongest matter consumes weaker, and weaker life forms have no chances of survival in the universe, but to surrender. But the universe doesn’t create a matter or a life form without a reason and purpose to play in its cycles. And when the stronger life forms threaten to extinct the weaker life forms and invade its space, the role that was meant to be completed by those extinct life forms becomes pending, thus creating an imbalance in the cycle of the universe.
As per many religious scriptures, a heaven is a place where divine beings gods exist, who will protect the law and order in the universe, and hell is a place where evil demons do exist, that threatens to harm other life forms in the universe. And we come across a lot of mythological stories from different religious scriptures across the planet, about the wars between gods/Angels and other demon creatures descended from hell, who had invaded planet earth.
and hell, some religious scriptures like Hinduism, Jainism, Buddhism, has detailed explanations on arrangements of different realms in the universe, where the universe is divided and charted into different realms.
According to those scriptures there 14 realms/Lokas in the universe, that includes & heavens and 7hells

7 heavens:

  •          Brahma Loka: where the creator Brahma resides ( where creation took place )
  •          Tapa Loka: A place that has the highest vibration of creation, the beings existing here have no shape or identity.
  •          Jana Loka: The first beings to have a physical body, with the highest lifespan in the universe.
  •          Mahar Loka: This is the special realm, where the sages who have accomplished great feats from any of the below realms reside.
  •          Svar Loka: The realm where the lord Indra/Zeus with his companions exist.
  •          Bhuvar Loka: A realms where other advanced life forms exist.
  •          Bhur Loka: A realm where earth and other billions of other life-giving planets exist.
    A picture of vishnu displaying all lokas of the universe in his body

7 hells:

  •          Atala
  •          Vitala
  •          Sutala
  •          Talatala
  •          Mahatala
  •          Rasatala
  •          Patala

It is mentioned in the book of Vishnu Purana that upon a visit from Narada (celestial messenger) to lower worlds, he notices that the lower worlds (Hell) were much more advanced than the heavens in the fields of technology and architecture. As the beings in the lower realms are strongly attached to materialistic comforts than the higher realms.
Because the universe is filled with powerful life forms, each having its unique character, strength, and weaknesses, a clash between them would bring a devastating effect on the universe, so a special governing body was formed, that would act as a committee/forum to discuss and resolve the disputes between planets, realms, and life forms, and to protect weak life forms from invasion or overexploitation of resources and maintain law and order in the universe. The governing body will be attended by members from all the realms, and the life forms belonging to weaker realms that are not capable of space travel will be attended by representatives of the committee.
zeus/indra | olympian god
And the committee will be headed by Zeus/Indra, in Sanskrit Indra is not a name, Indra means who is in control or who control devas/Angels and the universe, according to the ancient scriptures, the position of Indra/Zeus is not permanent or hereditary, anyone from any realm of the universe can decorate the seat of Indra/Zeus, until he is/has fulfilled the requirements and duty of protecting the righteousness. The one who decorates the position of Indra also possesses the most powerful celestial weapon called Vajrayuda (Thunderbolt) to assist him in fighting the demons that threaten the law and order in the universe.
So, this could possibly be the reason why gods/Devas interfered in the affairs of earth in the ancient times, because the earth is in the Bhur Loka, which is the lowest of the heavens and closer to hell, and most prone to the attacks from the advanced races of aliens from the lower worlds(Hell). Being the strongest beings in the universe, it is their duty (Dharma) to fight to protect the weaker beings in the universe.
“Sarve Jana sukhino Bhavantu” - Let the People of the world be happy!