[afdbcreid]

> Readable and debuggable macros

I agree this is a concern. However, proc-macro errors can be improved, and the people that should (and can) do so are their developers, not the compiler developers (although if they can it will be good, but I doubt it).

> Floating point operations reproducibility across environments.

I'm not proficient with blockchain, but Rust's floating point is and will always be what the hardware provides. Libraries can provide custom float types.

> Zero-exception safety mode checking at compile-time.

This is what `Result` is for. If you want to also catch panics, you can use `std::panic::catch_unwind()`. There is no good way to prevent them at compile time, and cannot be without major changes to the language (though see https://github.com/dtolnay/no-panic).