Steve Larkin (38)- Has a higher career batting averge in the majors than his brother. He probably brings it up at every family gathering.
Joe Oliver (46)- According to similarity scores, the most similar batter in baseball history to Joe is Bo Diaz.
Barry Bonds (45)- I'm not saying he would have, could have, or should have, but if Bonds had played another year he would have crossed a bunch of statistical milestones: 3000 games, 10,000 ABs, 3000 hits, 2000 RBIs and maybe even 800 homers. Maybe 700 intentional walks, too...
Tommy McCarthy- In 1946, a bunch of 19th century players were tapped for the Hall of Fame. McCarthy was one of them, and looking at his record it's really hard to see why.