I would propose:
Notify of available updates on every login.
Automatically update (critical) security updates.
Do not automatically update (major) versions of products liable to cause havoc.

Most server systems have quite infrequent logins, so above would be acceptable midway.

i like the idea of seeing what updates are needed on login.
Since this is a server I wouldn't automatically install any updates. A service might need to be restarted after the updates.

i like the idea of seeing what updates are needed on login.
Since this is a server I wouldn't automatically install any updates. A service might need to be restarted after the updates.

We sort of already have this, since we install Cockpit's package management tool by default, which will always show pending updates.

It's really not common to log directly into a server unless something is going wrong. A better solution for managing updates would be to use something like Red Hat Satellite, but I'm not sure if that has full support for Fedora Server. It's worth looking into.