You're not just looking for laughs, but you're trying to do the characters first, and then the laughs come afterwards.
When I was growing up, we learned our history almost as lives of the saints. And it came as a shock, "Oh, Jefferson had slaves?" It always comes as a shock to us that elevation to the White House didn't somehow cleanse them of all their deep character flaws.
[C. Montgomery] Burns is much purer evil than Nixon was. I think it's the purity of his evil that attracts me as a comic character.