He doesn't have a doctorate but Joker is stated to be an expert chemist almost on par with Scarecrow, just different focuses.
Ra's Al Ghul is 600 years old, a master of multiple martial arts and languages, has first-hand knowledge of all kinds of history, and is the leader of the League of Shadows.
And I'd be willing to throw most supernatural villains in the list too.
The city is absolutely cursed. Wasn't it originally built on or near a native American burial ground or something? Or is that just Grundy and his swamp?
Plus the multiple Lazarus pit thing.