I remember vividly when a user couldn't access his smb drive from Windows because both his printer and also the computer's case came with one of these multi-cardreaders with n slots and the drive letters collided. That's when I learned that smb drive letters don't even come from the "global" pool of drive letters, because, and this is obvious in hindsight, they are a per-user affair (credentials and all that).

I think the concept of drive letters is flawed.

Even Microsoft appears to agree with you, given that drive letters are symlinks. It's basically legacy, there's just no plan or reasonable path forward that will remove them.

I always tried to point people to DFS w/ the FQDN path. We added a shortcut to the user's desktop that pointed to their home folder on the DFS namespace.