Provide finer grained permissions configuration

If I understand Bitbucket correctly, a project or repo currently has three user levels:

• read
• write
• admin

The admin can give access to users to his or her project, and can do some very sensitive tasks, such as removing a branch permission that prevents users from deleting the master branch.

It would be great to have a user level that allows users to give access to their projects or repo without giving them full admin access.

I haven't found a way to do that... if there is, please help and close this suggestion