We tend to do a lot of experimenting.
We have both Google Authenticator setup (easy), and SAML against Azure AD (difficult to setup) - and we have MFA enabled for Azure AD, so that uses the Microsoft Authenticator.
NPS+Azure AD MFA is a pain because of the lack of logs and diagnostics when things go wrong. If you want MFA for client VPN use a third party solution, like the Duo RADIUS server.
If you want to enable "global" MFA for the Dashboard use a third party SAML provider like DUO. You can also use AzureAD if you don't mind doing a bit of extra setup work and Googling.
We use AzureAD because we already use Office 365, and it was more convenient to have the one system for everything.