It just seems... lazy. That the writers don't have to explain anything because a God can revive characters and give them visions of what to do when it is required by the plot. If that is satisfying storytelling to you then fair enough but I prefer the show to use different narrative devices. God and an afterlife rids it of consequence and weight.
It doesn't do anything interesting with the idea of a God. It's just humdrum monotheism presented in an unambiguous, uninteresting way.