It seems like the struggle here is trying to use Rust transparently/automatically from another language instead of just make bindings easier. I have found that trying to auto-FFI existing Rust types is not the best for languages because there is often an impedance mismatch with how the language treats things and how Rust does. Therefore trying an always-works transparent binding may inevitably end up with people asking for more flexibility to fit the language better (e.g. controlling lifetime semantics, type mappings/copying, etc).

I think it's clearer to take an approach like Neon and PyO3 and other FFI-to-lang helpers do where you just make it easy/safe to write these Vale functions in Rust.