This type of reasoning makes no sense to me. If you genuinely believe God exists (and is somewhat similar to the description in the Bible etc), then the question of how useful the concept of God is for worldly affairs becomes irrelevant.

So if you're asking about the usefulness of God and considering to get rid of the concept, that already implies you don't believe in God in the first place. But in that case, the usefulness also becomes irrelevant. If something is a falsehood, you should get rid of it either way.