While looking for a solution for this I came across Gate. It automates OpenVPN profile creation behind OAuth and supports MFA. It’s also got an admin console for user management.
Here is a blog post from the developers outlining its use-case and features.
UPDATE 06/2019 – Pritunl is now my go-to solution for this. It supports automatic OpenVPN profile generation behind Google Auth, and provides a cross-platform client that makes setup easy with unique URI’s. The user doesn’t auth with Google to connect (a PIN can be required) which could be a downside for some, but I find the ease of use great for smaller teams.