It's strange that Scarlett, despite trying to destroy the island and everyone on it, isn't even arrested but just disqualified as normal.

Dick Hardly is not the evilest PPG villain. HIM is. HIM attempted world genocide (mundicide), and while Dick is not as evil as HIM, he has fewer resources than him. That's one of the main reason why he is Pure Evil. HIM has redeeming qualities, making him to count as Near Pure Evil.