Restrict access to channel e-mail settings
As a team member, I am able to change a channel's e-mail settings between allowing only team members to submit messages and accepting messages from the tenent-defined domain.
Personally, I would prefer this change be restricted to Team admins. If the ability for member-level accounts to modify this setting is intentional, desired functionality, I would like an option on the Team "member permissions" setting to allow/restrict members from doing so.
I would also prefer an org-wide setting to whitelist email domains rather than doing it channel-by-channel, which is only possible for a team member/admin anyway.