I really must disagree here. Maybe my strategies are vastly different, but usually, I can't aford all those -4 "You have a heathen religion" penalties. That alone makes Secularism pretty good. I generally jump for at the first chance, sometimes even building the Shwedagon Paya to get it. Usually, my empire gets too vast, and I need to get rid of the revolution penalty for non-state religions. I guess if you aren't playing with Revolutions, I would agree with you, but who does that now.