If you're getting to many emails, the problem isn't your client. The problem is your organization. Stop making yourself so available to everyone. Stop insisting

If you're getting to many emails, the problem isn't your client. The problem is your organization. Stop making yourself so available to everyone. Stop insisting on being CC'ed on every discussion. Give employees autonomy so they don't have to get your approval to do every damn thing. Stop being the point of contact to every client. You don't have time to personally deal with everyone.