Ninja Turtles -- absolutely! Leonardo's the Leader, Donatello's the Smart Guy, Michelangelo is the Heart, I think, and Raphael I'm a bit less sure about -- Big Guy or Lancer? (or both?) But yeah, I think they do feel like a Five-Man Band, even though there are only 4 of them.

Leverage I've only seen one episode of, so I don't have a good feel for the dynamics, but from fandom osmosis I gather that there's a Big Guy (Eliot, right? he's the hitter?) and a Smart Guy (the hacker - Hardison?) at least?