All the library does is facilitate the build process.
I think there's possibly some automation that can be added once that whole stuff stabilizes properly. From Rust it's already possibile to automate exposing a C header via cbindgen, so it wouldn't be too hard.
JNI ultimately still provides the most complete set of capabilities (e.g. calling back into Java).
For the rust-maven-plugin, we've accepted a PR to build binaries and we'll continue accepting PRs for any future enhancements such as the one you're mentioning.