The hot loop you're describing is the whole reason you'd want to reach for a systems language over Python: once the orchestration lives in the interpreter, you pay for the round-trip every iteration. There are now two tile-based ways to do that in a compiled language: CUDA C++ Tile and cuTile Rust. Both get you out of Python and into the same tile model. What cuTile Rust adds is the safety layer: Rust's ownership model gives you compile-time memory safety and data-race freedom (we prove it in the paper), which the C++ path doesn't. So if you're moving off Python anyway, the real question is whether you want those guarantees.
How much of gfql maps cleanly depends on your specific ops and how the pipeline's structured. Happy to dig into it if you open an issue.