The thing I loved about the Dalek in "Dalek" was just how conniving and manipulative he was. He could have killed everyone one at a time, but no he thought it more effective to electocute loads at once!
I'm not an expert on the original series, but it was certainly the only time in the revival a Dalek demonstrated an understanding of emotional manipulation and psychological warfare. "Have pity!" "I am glad I met a human who did not fear me. Please pat me on the head with your arton-energy-soaked hand." "What use are emotions if you will not save the woman you love?"
Compare that to "Bad Wolf," when the Daleks attempted to coerce the Doctor by threatening to kill his "associate." I suppose buttering up the businessman in "Daleks in Manhattan" sort of counts, but that was the Cult of Skarro, who are supposed to be more perceptive about these things. Even the Supreme Dalek in "Journey's End" was pretty ham-fisted in his attempts to twist the knife with the Doctor ("Do you feel sorrow? Rage? Then if emotions are so important, surely we have enhanced you!"), especially compared to how Davros was able to make him cry later.
