Grafana move really fast. Very practical. It first if I remember use ElasticSearch/InfluxDB to store its config itself. Then move to its own SQLite. Then MySQL/Postgres. Eventually add alerting. Add multiple data source.
Nowsday my team even use its with SQL for a cheap version of Periscope/Mode.
Then now they figure out this log thing. ElasticSearch is great but try to run it yourself. On a 50 nodes k8s, I bet your first ES config will down after 10mins the first time FluentD come up and send all the log under the sun since the cluster come up
Given that Grafan guys know how to deal with visualization, I trust them to deliver a great experience again for log.
Look at their history, I'm going to bet hard on this.