Traditionally, fire was for heretics (See: Bloody Mary ) and traitors were hung, cut down while alive, and quartered, sometimes with crazy additions of being disemboweled and/or your dick cut off while alive then being forced to watch them burn them in front of you.

That's why in other parts of Europe (that were still Catholic) they burned their "witches", and why England and the American colonies didn't, as hanging became the method of choice after the English Reformation.

That's not true, there were witch executions in Spain and the idea of witches was accepted as true - however, the general point of the witch hunts being less severe in Spain is true, as the Inquisition discouraged the hunting of witches and did not allow the secular courts to conduct trials. Those witches who were identified tended to be forced to conduct repentence.

The burnings were for the crime of Heresy. Not Witchcraft.