Unkind words shouldn't be a crime in and of themselves - that includes slurs.
It makes sense to criminalize stated threats of violence or persistent targeted harassment, but generally free societies should err on the side of not criminalizing speech if possible.
My nation and the elders of my family historically responded to proponents of hate ideologies with hot lead and HE artillery shells. Letting them get off with nothing more than a minor criminal record is an extremely generous offer.
It makes sense to criminalize stated threats of violence or persistent targeted harassment, but generally free societies should err on the side of not criminalizing speech if possible.