I'm not sure if he's been mentioned but Paul Simonis would be a coup in my opinion, young, available and did some great work at Go Ahead Eagles (highest ever finished and the Dutch cup), he didn't do much at Wolfsburg but he only got 12 games and they're pretty terrible anyway.
He's also a notable egg, Guardiola, Maresca, Slot and Kompany prove that being bald is directly linked to winning titles.