I like how, in Missive, you can see your inbox, the open e-mail, and the calendar.
However, I love the natural language feature in Fantastical. This allows adding a calendar invite by typing in natural language.
For those who don't know what this is, please see link on youtube:
If Missive had this, I would have little reason to use Fantastical. Also, Fantastical is not SOC2 certified giving missive a big leg up.
If this has been mentioned, I apologize, but I couldn't find this feature request.