There is certainly less “Faith” (in the Kierkegaardian sense) today, but I don’t think that springs from our culture. It comes from developments in epistemology and phenomenology, and Descartes is probably to be blamed (or thanked) for much of this. Since the structure of experience and consciousness is such that we can only relate to the world from a first-person perspective, then what we can know for certain about the world must necessarily begin from the knowledge of our self. We are inextricably centered within ourselves, but that doesnt necessarily make us all “self-centered.”
Narcissism, after all, is not contemporary. So I don’t think it’s fair to say that the promulgation of “faith in oneself” (as I use the term) has led to greater narcissism. The river wherein Narcissus caught his reflection, after all, should not be blamed for his excessive self-love and self-involvement. It might just be that because there are ubiquitous “technological mirrors” today the narcissism that seems to be apart of the human condition is given far wider expression.
Would a return to “Faith” or an acknowledgement of the existence of a higher power remedy this? Probably not. I’m not inclined to accept that belief in a conscious trasncendental being is a panacea for these human foibles you mention. We had all these issues even when the vast majority of people believed in one (or more) Gods. Narcissus himself was the son of a God.
I think a lot of people would have no problem responding to you by saying: “Right: there is no higher power, material existence is all there is, and faith in oneself is all we have — so what?” I would disagree with these people. Is there a higher power? I don’t know. I have no way to prove this either way (although when I get mystical and reflect on the subject I have a strong feeling that there must be something, but I just can’t make the full leap to a place of certainty). Is material existence all there is? Of course not, the infinite world of ideas is arguably just as large as the physical world of matter. Is faith in oneself all we have? Certainly not. Because even though we are stuck within ourselves and can only perceive and understand the world as ourselves, eventually we must become humbled by the realization we as individuals cannot reconstruct all of human understanding — we must have faith in the work of others; moreover, we must also accept the fact that we will never know or understand many or even most things. But it is the knowledge that I can have faith in myself that allows me to trust the faith that others must have in themselves too. This is what gives me faith in humanity.