Apple Mail's not quite as customizable, indeed. Maybe close though. I made a table comparing different email services on the MacPowerUsers forum a while back.

Apple Mail's not quite as customizable, indeed. Maybe close though. I made a table comparing different email services on the MacPowerUsers forum a while back. It's in need of updating but might be handy: https://talk.macpowerusers.com/t/icloud-mail-fastmail-gmail-what-are-the-differences-the-email-service-feature-comparison-table/24929 https://talk.macpowerusers.com/t/icloud-mail-fastmail-gmail-...