Why does my home directory location keep reverting to the previous setting?
I suspect the problem was me trying to change my home directory from my account. I was able to make it work by:


Creating a new user on the system
Giving that new user Administrator privileges
Logging out of my account
Logging in to the new user account
Editing my account's home directory from the new account


After that was done the changes stuck and my home directory is now on my HD instead of SSD. I kept the other account around for now, though I stripped it of Adminstrator privileges.