There is no golden path here. Checked exceptions for division would make a lot of Pony code objectively worse. Unchecked exceptions are great for PHP, Haskell, Rust or Go, but Pony is trying to do something different - to literally make it impossible to panic in an operation without describing that in the type system. The ergonomics of divide by zero in this context are absolutely debatable, not an issue to dismiss out-of-hand.