For a iconic hero?
Uther the Lightbringer. From the Warcraft franchise. Fear not! The Light is with us
For most evil villain?
John Irenicus. From Baldur's Gate 2; Shadows of Amn. Between being voiced by Alan Rickman, and having some of the most well written dialogue and plot EVER for a villain, noone else even comes close. It is made even more poignant because in the original Baldur's Gate, you had just defeated a great evil. And to realize that he was so far out of your league that he could capture and imprison you without breaking a sweat, I don't think I have ever been more motivated by a game villain to go out there, get more powerful, come back, and KICK HIS ASS.