Have you checked out Stytch? I'm more than a little biased as the founder but would love to hear any feedback you have if you do. I thought your blog post covered a lot of really important points that are often forgotten when evaluating auth.
We support both a user changing their own email and with our embeddable admin portal, you get an out of the box flow where your customers' admins can update the email (and any auth setting) for other team members.
We support both a user changing their own email and with our embeddable admin portal, you get an out of the box flow where your customers' admins can update the email (and any auth setting) for other team members.