As you can see from this piece of news, an encrypted email service does nothing for your privacy. But at the same time it limits you and makes you a captive user. Which is ironic considering that's probably why you left Google.
You don't have to self host. Just use a regular email service, perhaps hosted in a country with decent privacy laws if you want, but download your email on your PC instead of keeping it online on theirs. This way you get to backup your email too.
The most simple way to do this is to pull your email with a POP connection but set it to only delete messages after a few days not instantly (this way you can still access them over IMAP for a while from mobile or webmail).
Another approach is to pull your incoming email to your server, set up your own private IMAP server and webmail, but use the service's SMTP. This is a form of email self-hosting that gives you the best parts of privacy and control but you don't have to deal with the risk of having your SMTP blocked for spam.