kroberton

I'm using my own domain anyway. When your last name is your domain, it gets impossible to impersonate you with any free service. And as it's only 1 Euro, it's also cheap and easy.

In Protonmail client is open source, server and apps are not.

Yep: https://github.com/tutao/tutanota/

Devs say they want to publish the app on F-Droid. https://tutanota.com/blog/posts/secure-mail-open-source

Avoiding links is the ultimate goal, hopefully Tutanota will integrate your suggestion or something similar. I've moved my entire family to Tutanota, which also works quite well. But you'll never convince everybody...

As far as I know self-destruct emails in Gmail are not end-to-end encrypted.

Agreed. And: https://tutanota.com/

Gmail used to be good alright, but then it started to ask for my phone number all the time. I've switched to Tutanota recently, much better IMO, particularly the new client: https://mail.tutanota.com/