Mickey Mantle is a guy who has recently gotten my attention because of his Disproportionate Power; he was a non-gigantic guy (just 5'11") who managed to hit some of the longest home runs in history. While some of that was due to an aggressive swing and great hand/eye coordination, it was also due to Mickey Mantle's swing and its combination of extreme simplicity and efficiency.
Elsewhere, I go into The Secret of Mickey Mantle's Swing in detail, but here are a few clips of Mickey Mantle's swing and a high-level explanation of why Mickey Mantle's swing was so exceptional.
Mickey Mantle's Swing
Mickey Mantle's Swing
Mickey Mantle's Swing
Mickey Mantle's Swing
In the clips above of Mickey Mantle, notice how Mickey Mantle gets to and holds the Vertical V. Notice how, rather than standing up straight and Dropping His Hands, Mickey Mantle Tilts and maximizes his Alignment. Finally, notice how Mickey Mantle Gets a Good Pitch to Hit. Instead of swinging at a pitcher's pitch down in the strike zone, Mickey Mantle looks for a ball that is more up in the strike zone and that will allow him to maintain his Alignment and just rotate into the pitch.
P.S. I have always wondered who influenced Mickey Mantle's swing. After looking at some clips of Ralph Kiner's Swing, it wouldn't surprise me if Mantle or his father spent a significant time studying Ralph Kiner's swing.