So, I eventually switched to Byzantium, but the KDE Live couldn’t deal with LUKS, so I had to go an unorthodox route: install a bare minimal Debian Stable from Netinstall, and then add PureOS keychain, replace the sources.list, and make sure everything is dandy with some pinning.
Now I have a proper PureOS, but - and this is where I will invoke the rage of 3 distros at once -, I also added - with proper pinning well below PureOS - the repos of Kali and Parrot, including the contrib and non-free sections.
* running from stones, continuing the argument from a distance *
All three distros track Testing, but in a safer, slower way, so it’s not as risky as running a pure Testing. But I also need some packages that are not available from the PureOS software collection. Main is always from PureOS, per pinning, no way that anything can replace those packages.
Why don’t use Kali or Parrot then? Because they still have some quirks that are focused on pentesting, while PureOS is focused on regular usage - but with some hardening included.
So, I have the best of 3 worlds. But otherwise, the selection of packages from Kali or Parrot are very minimal. I have not encountered dependency conflicts so far with anything that I need.