Is there a unified view of all my team inboxes?
Yes, the Team Inboxes unified mailbox. You can open it from the + More menu of the left sidebar.
Here is how it works:
When creating a team, you can define two types of users: Active members and Observers.
Active members receive notifications for all new messages and chat comments. They see conversations listed in the Team Inboxes unified mailbox and the team inbox itself.
Observers do not receive notifications and only see conversations listed in the team inbox. This is perfect for managers who want to monitor the work being done but don’t want to be flooded with notifications.
The Team Inboxes unified mailbox is helpful for organizations having a lot of team inboxes (e.g. one team inbox per customer) where it’s impractical to look at all team inboxes individually. Using the unified mailbox improves productivity.
You can read more here.