If one were to try to pare religion down to its common essentials, there wouldn't be much left. The only thing that I can see that all religions have in common is the symbolism of the union of masculine and feminine: in Christianity, Christ and His Bride the Church, who are waiting till the end of time for the wedding; in Hinduism, the union of Shiva and Shakti; in Judaism, Yahweh and the Shekhinah; in Sufism, the union of Lover and Beloved, or Allah and the soul; in Wicca, the union of the God and the Goddess; and so on. There are many values that different religions have in common, though.
If you do the Belief-o-matic questionnaire, you can see exactly how much your religion's beliefs and values overlap with others.
The different philosophy, theology, atmosphere, traditions, practices, meanings and mythology of different religions is what makes them unique. Some people call this particularity. It can be distinguished from exclusivity (the view that each religion is self-contained and does not need input from outside) and sectarianism (the idea that only your religion is true) by the fact that, while its practitioners love its unique features, they are prepared to acknowledge the worth of other people's traditions for them. Each religion has its own stories, its own colours, its own frequency for tuning in to the numinous; and each has blind spots towards certain aspects of the Divine (e.g. mainstream Christianity's is the inability to see sexuality as Divine and spiritual) but that doesn't mean we can't appreciate each other's stories and learn from them.