Thank you, everyone, for the replies. I appreciate it. As a software developer I consider myself reasonably smart, but discussions like this break my brain 

A follow-up, if I may: Given what you know about the math behind this: How confident do you feel having your entire Bitcoin wealth in a single wallet? (Assume you have perfect OPSEC and the only "risk" is an accidental or brute-force collision with your wallet address.) Just curious.

Thanks again!