To all religions/What makes you think......

[Belacqua]

To claim that science is the best way to know about the world, people being what we are, is not the same as saying science will last forever.

Yes, that's what I'm saying. Our current claims (including the one that science as it currently operates is the best way) may not last forever. 

If there is an all-powerful, all-knowing, perfectly-good God, we should be able to observe evidence of his actions in the real world.  An indifferent God, not necessarily.

According to your current framework for judgment, these things are true. And according to that view of things, there is no such evidence. This is what might change -- I don't know.

A lack of supporting evidence for any belief is justification for a lack of belief.

And any lack is a lack based on a framework for interpreting what evidence consists of.