Without concrete, testable and academic definitons of what a god is, what a god does or how we know a god has intervened in material reality, the best case for God's existence lies in philosophy.
But if the best case for God is in philosophy, then:
1. The best case for God is NOT backed up by science.
2. God is nothing more than a concept I make up for myself.
And if the battle comes down to philosophy, I will argue the case that methodological naturalism is vastly superior to any form of supernaturalism, and in particular Protestant Trinitarianism, as a basis for knowing about the world and informing morality.