At this time, there is no way to automate the process you are describing. Perhaps the only thing we could suggest, beyond the steps you have already taken, would be to create an event to send a notification to your administration email account when a new user is registered. Note that this would not indicate whether the user's email has been verified, only that an account has been created. Once registered, you could check on the user to see if they have been verified under the roles tab. Then, if you create a custom Authorized role, you could set the permissions for the community to only allow those with the Authorized role.