The Universe is what the Universe is

I don't know about the design part of your response -- are you suggesting God created the world complicated, with difficult-to-understand principles so as to give us challenges?

I think the universe is what it is; sometimes easy to understand, but the further we get away from what seems intuitive the more difficult it will progressively become to "understand."  This is predictable -- stuff at the cosmic large and cosmically small seem counterintuitive, demonstrable experimentally and often predictable mathematically, but still way outside our daily experience and therefore our intuition has no value.

There are two proposed "interpretations" of the double-split experiment, neither of which comes even close to understandability or acceptability to me at least -- the Copenhagen and the multi-universe or infinitely splitting multi-universe.  The first implies observer interference (even if the observer is just a rock) and the second is just way too extravagant to be acceptable with just one experiment available, although I will admit the experiment does give one pause.