There would be no point in changing the Declaration of Independence; it's not a legal document, its relevance is purely historical. And history should be preserved.
I don't particularly care about what's on the money... frankly if people want to get all offended about money, Andrew Jackson on the $20.00 bill should be the biggest problem, as he was involved in the genocide of Native Americans. If they want to change the pictures or words on money, it doesn't bother me as long as it's still recognizable and I can still use it to buy things.
As for the Constitution, there's nothing explicitly religious in it. Obviously some laws are shared between the Constitution and the Bible, like the prohibitions against murder and theft, but do you really think it would be a good idea to repeal those?