Creation out of absolute nothing is a metaphysical quagmire for theists anyway, since nothing must at least have the potentiality for becoming something. Since theists are stuck with potentiality, it might as well be something like a quantum vacuum.

Attaching a Creator to the boundary is metaphysical skullduggery.

Which is better: to achieve Nirvana, or become a Boddhissatva?

Physicists use 'God' as a metaphor more often than other scientists-- especially in popular writing, but in the technical literature as well. Of course, this is just a metaphor for order at the heart of confusion. A rational or aesthetic pattern underlying reality is far from a theistic God.

To talk intelligibly about modern physics, we have to admit the possibility of uncaused events.

In the popular imagination, the Big Bang is a great explosion at one time there was nothing, then matter erupted into previously empty space. However, the Big Bang is the beginning of spacetime itself, not an event in time.