It would be great to have a contact list inside Missive with some custom fields, like full name, email address, phone number and some others (customer ID as a string, bullets, dropdown menus, tags, etc.).
I would like to create a new contact when I receive an email inside Missive. Some fields, like full name and email address, could be populated automatically. This list could be synced with other services like Gmail Contacts, or could be made available for import and export in a csv file.
There was a topic on a sidebar with additional information about a sender. It would be great to see there an information about a contact from the contact list, with custom fields and previous communications.
Also you could add comments and tasks to contacts.