Baseball: Ken Griffey,Jr
when I was a kid, everyone wanted to be like Jr. He was absolutely the shite and awesome to watch in the late 90s.
Soccer: hardly a Barça fan, but definitely Messi. That little dude can turn absolutely nothing into one of the finest goals you've seen on a regular basis.
Football: call me a homer, but Drew Brees has put together one of the most exciting, pass-based offenses in NFL history, and it's absolutely beautiful to watch. He takes fairly average receivers like Colston, Moore, Graham, and Henderson and creates a god damned machine.