The universe is large and we are tiny, without the need for further religious superstructure. One can have so-called spiritual moments without belief in the spirit.
Genuine happiness consists in those spiritual qualities of love, compassion, patience, tolerance and forgiveness and so on. For it is these which provide both for our happiness and others happiness.
If science proves some belief of Buddhism wrong, then Buddhism will have to change. In my view, science and Buddhism share a search for the truth and for understanding reality. By learning from science about aspects of reality where its understanding may be more advanced, I believe that Buddhism enriches its own worldview.
After death the soul possesses self-consciousness, otherwise, it would be the subject of spiritual death, which has already been disproved. With this self-consciousness necessarily remains personality and the consciousness of personal identity.
We do not "come into" this world; we come out of it, as leaves from a tree. As the ocean "waves," the universe "peoples." Every individual is an expression of the whole realm of nature, a unique action of the total universe.