No, it wouldn't make sense. Coalton is a strict language.
I quite like Mercury's non-monadic linear IO + determinism semantics. You can subtype the world with insts and unify against the world-state pretty easily.
That would obviously make it easier to analyze and test and verify the program by first focusing on the pure part of it, then on the impure part. I'm not sure if that is possible in "strict languages" but perhaps.