I would prefer it if PIM was abandoned entirely and instead we could choose the actual parameters for both PBKDF2 and Argon2id, with secure default values for anyone (most people) who doesn't want to change them. I think PIM worked fine when there was only one KDF, but now using PIM for all KDFs is confusing, since it means different things for different algorithms. But it also removes the ability of the user to choose the parameters they prefer. With PBKDF2, PIM allows you to choose almost exactly...
Thank you for this new version. I also hope for Argon2 support for Linux.