The real question is thus, in my mind, not "Why is there something," but "Why isn't there nothing?"

Excellent way of looking at it. To my way of thinking, something has to be eternal, either a multiverse (?) or a UI. If there was nothing there should be nothing now. I don't buy the stupid stuff that nature abhores nothing so there always will be something created. How, created from what if there is absolutely nothing to begin with?