[@t2wave][@Zarkun]
What if I were to adapt on your first idea? Maybe in the midst of the power vacuum the dragons left, two noble families climbed to positions of power together, bringing order and peace to the aftermath of the Dragon King Festival. The Fiore family worked with the Flamels until the matter of the crown came into question, at first Nicodemus's ancestor was agreed upon to be ruler but then on the coronation day was betrayed (killed) and his family was banished? Still illustrious and really adds to the 'vengeful' part of him whilst keeping to RP canon. Would that work?