My email should be back in commission as I've fully worked the kinks out of my new personal email server.
I have at least something to show for it that might be useful to people.
Long story short, after running into some nagging problems getting all the pieces to come together, I wrote a script in parallel that configured a Debian email server from the vanilla install with all the settings a normal human would need for personal email use. It installs and configures Postfix (SMTP), Dovecot (IMAP), Spam Assassin and OpenKDIM (so you don't get spammed yourself). Check it out on Github:
So now my email is working and in the end, I configured it without manually editing a single file!
Check the readme, but I encourage you to follow the steps and try it out on your own server if you've been looking to host your own email. The requirements are listed. I might do a video on this, maybe even tomorrow, so if anyone wants to get ahead of the curve and try it out and see if it works, feel free to give me feedback.
I suspect it will work on Ubuntu as well, but I don't have a server to try it out on. Even if it doesn't I'll be adding more documentation and comments to the script to make it a useful instructional to read.
Work with mutt-wizard obviously too and that's my new email setup.