Have you given a thought to Nim? I've never used it in the embedded space, but it should work there nicely. It has Pythonic syntax, but it transpiles to C, so it should fit both your criteria. I'm not sure how the GC fits in, but i think you can turn it off if it becomes problematic. I'd love to see the comparison. Rust is powerful, but I'm guessing a good bit more complicated as well.