SQRL - A New Method of Authentication
Consider implementing a new (optional) authentication method called SQRL - https://www.grc.com/sqrl/sqrl.htm
Designed as a replacement for usernames and passwords, developed from the ground-up with security in mind, it has been 5-6 years in the making and can work right alongside traditional usernames and passwords if you or users are apprehensive about the roll-out and uptake.
It is free and is not reliant upon a third-party vendor.
Unlike traditional usernames and passwords it doesn't rely on the website owner to store secrets that could be lost or stolen by hackers and then re-used elsewhere - It is quite revolutionary and could change the face of authentication as we know it, it just relies on service providers to try, understand and implement it.
All the best,