Cody, great post!
The current beta of GPG4Win 3.0 supports symmetric encryption using a password. If using multiple passwords is really that important, why not try that? It’s free, open source and actively maintained. Yes, there’s a learning curve but we’re not talking trigonometric functions here! Learning to use the software should be easy for “average” PC users. (Similar packages are available for the Mac and Linux but I don’t know if they support encryption with a password.)
For sharing, I actually prefer the AxCrypt 2 procedure to GnuPG because it’s easier to explain to others. It’s simpler and no one needs to create a key pair. Unfortunately, PGP/GnuPG still isn’t that widely used, even after a quarter of a century.