I saw a comment about how the feature request belongs in partman-crypto. I'm happy to re-report this there if that is where it belongs.
> I agree that using the physical volume block device name is bad
> because this name may not be persistent.
Notwithstanding the merit of this I wanted to make sure it's understood this is different from my feature request which would be to change the installer workflow so that instead of selecting a LUKS label for me the installer prompts me for what I want the LUKS label to be similar to the way that the LVM configuration workflow works.
Also thank you for giving my feature request some attention.