There's a misunderstanding here. My point isn't that religion should be scientific, but that maybe people should be better critical thinkers. And the more critical we are, the less happy, content, or socially functional we're liable to be. Hence, there's a philosophical choice to be made about the purpose of life. Psychiatry makes such a choice and is therefore grounded on a philosophy or on a culture that values pleasure and productive social functionality (i.e. capitalism).

I agree that science doesn't provide us with a unified value system, but art can replace religion in that respect. What's crazy about religion isn't its appeal to values, but the arrogance and intolerance of many theists. What's crazy is to think that supernatural beings reached down into nature and gave us absolute, infallible answers. It's the attitude of many religious people that's arguably disordered, given some conception of human propriety.