Hi, I'm Philippe one of the founders behind Missive.
We've decided to refactor the way teams can collaborate in Missive and I would love to have your feedback.
We had many conversations with customers that made us realize the collaborative flow in Missive wasn't good enough for many simple scenarios most SMB face daily.
Here are some of the things we want to introduce and/or change:
1. Each team defined in a Missive organization will gain a Team Inbox. Shared accounts and shared addresses will be linkable to a team inbox.
2. Each team inbox will have a self-contained unified mailbox at top level of the sidebar, and optionally sub-mailboxes, like Assigned to others and Assigned to me:
▼ Sales inbox 
⎯ Assigned to me
⎯ Assigned to others
3. Each team will be have a group of Active users (like it's possible now), but also a group of Observers.
Active users will receive notifications for all messages received in their team inboxes. Conversations in their team inboxes will also be listed in their unified Unassigned mailbox.
Observers will not receive notifications for messages received in the team inboxes they observe and conversations in the team inboxes they observe will not be listed in their unified Unassigned mailbox.
Both Active users and Observers will be able to open the team inbox in their sidebar.
The Observer role is designed with managers in mind, the ones who want access to all messages, who want to monitor how the work is being done by the teams, but don't want notifications or having their own Inbox/Unassigned flooded with messages.
e.g. A user can actively work on 2 team inboxes. All the messages from those two will be available in her unified Unassigned, and she can also observe another team inbox pinned to her sidebar. She keeps the benefit of the unified view for the two accounts without it being polluted by the one she is only observing.
4. When assigning a conversation to a team from the assignment menu, instead of moving the conversation to every team member’s inbox, Missive will move the conversation to the team inbox. So any team member can assign themselves and take care of it; other members will no longer have the conversation in sight. The assignment menu will look something like this, where Sales and Production are two different teams on Missive:
Assign to Sales
Assign to Production
[ ] Assign to Phil
[ ] Assign to Bob
[ ] Assign to ...
Mark as closed
5. Unified “Assigned to others” and “Assigned to me” mailboxes will lose the ability to have all of your accounts sub-mailboxes opened. We will advise organizations to use team inboxes if they still want the ability to segregate emails received in different accounts from the sidebar.
6. A conversation can be linked to only one team at a time. A conversation can be moved from one team to another team inbox manually or via rules.
Thanks so much for your time and potential feedback! :)