There's nothing logical in God first-cause arguments.Quote from achilles28:
I wouldn't consider the probability of the existence of God on par with that of Leprechauns or talking Zebras. One is a logical first-cause to an astonishingly orderly universe. The other two are random creations of the human mind that have no other (seeming) purpose than that of being conjured to prove a point. To wit, you might say the concept of God is just as nonsensical, and I would definitely say it's not. Either the universe created itself (matter coming out of nothing), or God created Himself (God created out of nothing). Or, one could argue the physical universe always existed, where the theologian would argue God always existed. Ironically, both the atheist and theist are forced to share a similar faith in supernatural concepts to explain first-cause. That in itself, is indirect proof the universe is of divine origin.
But, to answer your question, yes, I think unicorns are definitely possible (just a horse with a single horn on it's head). Leprechauns, not so sure about that one...
Also, an astonishingly orderly universe is exactly what the universe shows itself not to be, once you start considering what goes on away from the astonishingly narrow view of a simplistic personal perspective you outlined.
Neither is a universe coming from nothing to do with matter coming out of nothing as you suggest.
Stephen Hawking explains how the universe was quite capable of launching its existence on its own. There is no such usefully equivalent account for God, talking zebras or anything supernatural being able to do that.