My goal is to kick start some things around the Rust language for data science / data analytics and projects like this help to showcase what Rust can do. See my original blog post for more context: https://andygrove.io/2018/01/rust-is-for-big-data/
Interestingly I’ve had the same observations that you’ve had about the work the Spark project has done to work around the JVM. And is also been idly wondering what a native-first distributes data processing framework would look like and how it will perform. I’ll be really interested in seeing where your project goes.
It will be tough, and next to improbable, to match python's ecosystem. Maybe a way into it would be to marry the two.