I suppose if it were possible to separate the three completely it might be an enjoyable excercise to speak only of religious doctrine/theology/teaching apart from culture and politics. I propose a kind of game for all of us, if you are game

to do it.
I propose that we attempt to discuss religious teaching without recourse to either the culture those teachings influenced and/or were influenced by and the politics that interplay with the religious teachings. I don't think that the three are separable in expression but for an intellectual excercise let's try.
If I were choosing the most advanced set of teachings as far as pure intellectual achievement I think I would choose Sanatana Dharma, popularly known as, Hinduism. They seem to have a clear understanding of how economics works through the Caste System. They are willing to live their lives in the tension between knowledge and mystery when it comes to creation. They have a very strong sense of what happens when desire overwhelms and are patient with each other enough so that if you don't get it right in this life there will be next and a next until you do. There is such a wide range of religious expression that even a Monotheist, though not natural to the philosophy, could find a home in it.
But wait. If I were to choose a religion based upon pure rigor and discipline I would choose Buddhism. Rarely has a religious leader been so focused on one thing as Siddhartha was. The question of suffering has been a bugaboo to all peoples for all recorded history. Yet, Buddha discovered a key and kept to it throughout his life. They are a missionary religion, the first in history, and have done all of their work without shedding another's blood. Their focus upon quiet is much to be admired.
But wait. Confucianism taught respect for elders and for society the likes of which few other religions have ever seen. Taoism finds the harmonious way better than any other.
But wait again. What if you truly do believe in and find satisfying some notion of intentional creation. Where better than Judaism. They focus upon God's revelation through the acts of humans. Very ingeneous.
But wait if you wish a world wide community no concept for this surpasses the ummah and it even accommodates those who don't believe through Dhimmitude a system designed to help minority cultures find happiness in being led by another culture. Their focus upon devotion to God is unsurpassed. We could all do well to pray at least as much as the faithful Muslim. Everything about their beliefs, apart from their practice, is admirable....
Except for one...
But wait. If you want a religion that is monotheistic, if you believe in purposeful creation, if you wish to serve a God that has sacrificed for you, nothing beats Christianity. The simple doctrine of the Incarnation of God is incomparable.
Christianity does not promote a God who sends only books or who only commands from a mountain. Christianity trusts a God who entrusted Himself into our hands and even though we rejected Him His sacrifice rescued humanity from certain destruction.
Much more can be written about each of these religions and about other religions. None of their teachings of themselves should make us fearful.
I invite your comments.
Dan L