In the past two years I have developed a rather complex emailing solution. I’m making heavy use of the codeunit 400 SMTP Mail which is now longer available in the new version.
So it’s time to make myself feel confident with the new email features. For a quick start I can recommend these two blog posts
https://dankinsella.blog/developing-with-the-new-enhanced-email-feature/
ERP and BI 