I've been using ArchLinux for ~14 years now, previous to that I used Slackware and Gentoo. IMO it's better to be simple, yes there aren't any guarantees but worst case scenario I can rebuild, run my install script (which might require a few tweaks if it's been a while since I setup a new system), push new keys etc and then I'm up and running again in ~15 mins. i.e I think it's easier to repair or replace a simple system than it is to try work out how to do novel things on a complicated but safe system.
I intend to try NixOS at some point as a foray into these more complicated but "safer"/transactional/immutable/deterministic systems but I just haven't found the motivation yet.