Invoking a god for creation creates more problems than it solves, because now you have to ask, who created god? Since a god must be more complex than his creation, you created a bigger problem to solve.
I believe the current thinking for the "cause" of the big bang is that there was none. That's not unreasonable given how randomness is inherit to quantum mechanics. Also, before there was matter/space, there was also no time for a cause to occur in. While scientists may not fully understand the big bang yet, I'd feel much better betting on a natural, simple explanation than a "god of the gaps" belief, which has been shattered every time science advances.
Any belief about the origins of the observable universe rest on a leap of faith. It doesn't matter if it's God or a quantum fluctuation, there is no way to know about anything prior to the origin of the universe (assuming there is one). So it's not a "god of the gaps" explanation, since there is not actually a gap there.
If you claim that the cause of the observable universe is a natural phenomenon like quantum mechanics, then it necessarily raises the question "where did the laws of quantum mechanics come from?"
The idea that quantum mechanics simply exist for no reason at all is no more plausible than the idea of a creator.
Well, where do physics come from? That's a huge problem right there.
As for the creator of God, that problem is easily solved with the bible: God is the one who is. He is the only one who always was, and always will be. He is everything and the cause of everything.
I believe the current thinking for the "cause" of the big bang is that there was none. That's not unreasonable given how randomness is inherit to quantum mechanics. Also, before there was matter/space, there was also no time for a cause to occur in. While scientists may not fully understand the big bang yet, I'd feel much better betting on a natural, simple explanation than a "god of the gaps" belief, which has been shattered every time science advances.