Have you heard of GreptimeDB? I am the creator of GreptimeDB. It's open-source and compatible with InfluxDB Line Protocol but only supports SQL as the query language. And it wants to support all types of time-series data, including metrics, logs, and events.

InfluxDB is a great project, but as you said, the v3 migration is painful and is still WIP. About the performance, We already did some benchmark GreptimeDB vs. InfluxDB v2, you can find it in our blog.