[_carbyau_]

> More generally we would probably require freedom from physical harm by non state actors

In theory that is covered already by laws against physical violence in whatever form they take.

> freedom from employment consequences

This crosses the line into private actions and property. Unless you mean government employees maybe? I don't think you will find many private employers who'd support the idea they'd have to keep employees no matter what they say, privately or publicly as that could lead to significant harm of the business reputation.

You've already got libel, perjury, obscenity, harassment limitations on "free speech". Just accept that it is not perfectly free and the reasons why are generally(feel free to pounce on the exceptions) for societal cohesion.