User email visibility set by groups/space

Problem Definition

Currently, the 'user email visibility' security setting is global to all wiki spaces on a Confluence platform.
Some of our wikis administrators are requesting for enabling 'visibility' and other ones request for disabling.

Suggested Solution

Create a new Visibility for emails, for example, set this to work with space/groups of users.
Instead of having a global setting, would it be possible to set this parameter:

• either per space
• either per groups of users

Why this is important

So we can set the email visibility accordingly to each user needs