You may already be familiar with the principle of parsimony, or Occam's Razor. The eponymous idea is that explanatory "entities must not be multiplied beyond necessity" though surprisingly, those words aren't found in any of Occam's writing. The earliest attribution may actually be to Aristotle (384-322 BC), who wrote that "we may assume the superiority, all things being equal, of the demonstration which derives from fewer postulates or hypotheses".
Probability theory (Bayes' theorem, in particular) mathematically proves that the more simple explanation is the most likely one (see chapter 28), but intuition is helpful here, too. If an explanation requires 6 steps, then for that explanation to be true, each step must be true. All else equal, another explanation requiring only 1 step is therefore, more likely to be true.
But what exactly are explanatory entities or steps; what precisely is meant by simplicity? If just the fewest items is what counts, then isn't solipsism a better explanation for my experiences than realism because the former only requires that I exist while the latter requires that everything in the real world exists? And isn't one God a better explanation for existence than many brute natural laws and particles interacting?
compatible with Catholicism, especially if you're prepared to jettison a straightforward reading of the Bible. But if that's ok, why remain keen to keep carrying such extra explanatory baggage when it's merely possible? Given what we know now, it seems that a universe without God is just more probable than one with Him, and one of the important reasons that that is so is that a universe without God is a simpler one.