If you don't know the discworld books by Pratchett, Granny Weatherwax it the most formidable character. She is a witch, but doesn't generally use magic to solve problems; preferring to use persuasion and manipulation. In saying that her magic is extremely powerful.
Maybe a bard with huge wisdom, persuasion and intimidation.
you're thinking about it wrong. She tries as hard as she can to never use magic. her one spell she uses is a fancy Magic soul jar spell and maybe detect magic. For what she does you probably want a psionic.