There really isn't a good self-hosted solution for build metadata/metrics, unless you write something yourself. It would be interesting to see a GUI dashboard for Drone/whatever builds and pipelines.
1. Detect broken builds. It is better to actively notify somebody by mail, chat, whatever.
2. Prevent broken master. It is better to reject the pull request/patch before it becomes a problem.
3. Analyse the system. It is better to download the data and enable the use of whatever analysis tools are suitable.
They can show non-event information such as build time trends at a glance.