I was thinking of deploying Tailscale for lazy VPN Mesh Networking, but my opinions for SSO are Google, Microsoft, Microsoft in a different hat, Apple... or setting up a new OpenID Connect provider, which makes this project instantly more complicated... but potentially more fun/publishable?
@kkarhan I already run pfSense, the Tailscale idea is for potential client projects!
(I write tutorials and docs as one of my gigs.)