Just finished Overture

I played Overture after finishing the base game. To see the changes it made, do I need to restart the base game? If so, is there anything I should make sure to do before restarting? I already reunited with Rosaura, unlocked all records you can obtain on a first playthrough, completed all questlines, and went into the secret room. I have yet to buy the Pale Knight, though. Other than that, I've done everything in the base game as well.