Redheads are naturally inclined to have magical powers given their unique differences.
Curly red locks! Hair is an extension of the nervous system. With those coils of red curly locks, redheads are attuned to the energies of the environment, giving them a sixth sense. Red hair contains more iron thus having better antenna capabilities to sense danger for example. There was a dynasty in 6th C France of redheads known as Merovingians with long red curly locks known for their shamanic abilities. In Norway, legend states you can tell a witch by her red hair. During the Inquisition, 45,000 red-haired women were burnt at the stake. Hair is a source of power too, remember Samson and Delilah!
Sensitive to the environment. Redheads can detect temperature change and pain better than other hair colors. Heightened senses such as smell can forecast the weather. Being able to sense pain relates to a natural empathy that I know many redheads possess. The more in tune a person is with nature, the more their extra sensory perception is improved. Redheads are naturally gifted with ESP because of their environmental sensitivities. Strangely, redheads can handle more electrical shock than others. Scientists discovered this by subjecting redheads to shock therapy. I can only imagine the strange perversion the inquisitors had when torturing redheads.