Author here. This is basically the approach I am using these days to get maximum multithreaded performance for when it really counts (inner loops) [1]. I draft in Python and use Copilot to convert it to Rust, then optimize from there. However, Nim is still better than Rust in my opinion for simple scripts that I don't want to spend a bunch of time writing. Its only major downside is its relative lack of support for parallelism and bioinformatics (i.e., why I used Rust for a more serious project).
[1] https://github.com/Benjamin-Lee/circkit