Hi @Stefan, for a pre-built dashboard you might want to check out this one built by @thatdudedenis: There's FINALLY a nice dashboard for your n8n instance! (Built in Coda)
Apart from that, I personally am currently using n8n’s REST API as a data source in Budibase to display the last execution of a number of workflows. This is working fine as well and Budibase would be an open source tool, but it is a general purpose tool for building internal apps (and not solution specifically for dashboards).