Discord vs Missive

Discord follows the same type of interface design popularised by Slack, which is extremely clean and attractive, and doesn't clutter the interface with unnecessary chrome and cruft.

Unlimited amount of users.

Users can invite others to join a Discord channel via a web link, which means no installation is required to use the software - which is one of the big typical barriers to entry for social software.

Discord allows inviting people to a specific channel with a link. Links can be set to expire. Low effort/passive invite mechanics.

You can quickly send invites to people and they can join in using the web client without having to create an account or install the app.

Behaves and looks like Slack for regular text channels, but with the ability to create voice channels as well

Deny access, Deny write message, Allow read messages etc.

Discord provides an API for creating custom bots.

Discord has a wide variety of bots for things from airhorn noises to automated server management, to leveling systems for chat. The bot API is open and there are dedicated sites for finding bots.

Discord shows which game each user is currently playing, which among other things helps users to form PUGs with minimal hassle.

For those that are used to the way Slack (a similar chat client) works, Discord will be familiar in its use, which lowers the learning curve quite a bit for those that have switched or tried Slack before.

The support is limited but still exists. It's a killer feature for dev teams.

Discord prevents users from being DDoSed out of games.

Targeting roles allows for quickly requesting someone from a group e.g. artist, moderator, etc.

Ability to create channel categories for channels to sit inside of.

Free account have no tangible restrictions.
Premium account is just a way to say "thank you" to developers. And it work for all servers of discord (not as in slack). And it can be purchased by one who wants. In contrast to Slask, where all active members of the server should be "premium".

Have localization for many language, including Russian.

In Missive you can live edit an email draft with your teammates, the draft composer acts exactly like a Google doc. Each team member has a different color cursor.

The email section allows for consuming all of your email accounts in it, utilizing shared addresses (help@acme.com), personal work inbox (philippe@acme.com) and personal inbox (phil@gmail.com).

It’s important because the collaborative part of Missive becomes useful when users consume all of their emails within the app. You not only want to collaborate around emails sent to your company help@address, but also around the really important emails you most likely receive at your personal company address, like that really important email you received from a potential high profile partner.

Missive is also a team chat app. When using Missive you can ditch your email client, chat app and help desk.

Merge all email accounts in one unified inbox.

You can create multiple tasks per conversation all assignable to a single or a group of persons.

Nicely written software. Always works as you'd expect, beautifully designed, a classy piece of software.

Supports multiple organizations with one user login.

Know exactly if and when the recipients read your important email.

Supports Gmail shortcuts.