Philosophers are tricky. Many of them had ideas that were subversive or attractive or very influential, but the men (or women) themselves frequently not so much. And looking for Big Personalities among intellectuals is another needle in a haystack kind of search.
On the other hand,
Socrates was a Big Personality: a sculptor who became a gadfly to everybody, a philosopher who questioned everything, and influential on people as different at Plato and Xenophon. You could build an entire Leader and all their Bonuses just from two of his attributed quotes:
"To see the right thing is to do it."
"An unexamined life is not worth living."
And rather than Kant or Locke, may I suggest:
Voltaire - who never saw anyone in charge that he didn't want to deflate, and combined the talents of a philosopher, playwright, novelist, satirist, political commentator, and military historian all in the same pen.
As an alternative to Franklin with influence in both America and Great Britain (and Revolutionary France):
Thomas Paine - whose words appealed to American Patriots, French Revolutionaries and British Conservatives, three groups you could scarcely get to agree on anything other than Paine.
Sam Adams for the beer, but (quoting
@Zaarin, here)
Abigail or
John Adams for a Leader: either one will do . . .