Photo coutesy of www.marshallmatlock.com
The choice for top switch-hitter of all time is Mickey Mantle almost by default. You could get cute and throw someone else atop the heap, but that would just undermine all credibility.
Mantle embarked upon his major league career as a 19-year-old teenager from rural Oklahoma. He would end it as a legend of the big-city darling New York Yankees.
There is so much to be said about Mantle, who was one of the great five-tool players to play the game. He was not the most popular player among Yankees fans when he came into the league—replacing a legend like Joe DiMaggio will do that—but over time, he was so good that Yankees fans had no choice but to love him.
His resume is comparable to those of any that have played the game. He reached the All-Star Game 20 times in 16 different years (1959-1962 there were two All-Star games, and he made both each year) and won the MVP three times. Even more incredibly, he finished runner-up another three times, and in the top five another three times. Yes, the man was not human.
By the time his career was finished, his 536 home runs were nicely complemented by a .298 career average and a .421 career on-base percentage.
While he was a great hitter from both sides of the plate, he was better from the right side. From that side, he batted an insane .330, while he hit a "meager" .280 from the left. His power was better from the left side, though. From that side, he clocked 369 home runs and averaged .070 home runs per at bat. From the right side, those numbers dropped to 161 and .059, respectively.
Most mind-boggling is the fact that if his knees hadn't limited his production in the later stages of his career, he could have been even better.