How the Wizard of Oz Characters Are In Every Great Team

When writing the review for The Avengers, specifically making the list of his character archetypes, I realized the archetypes could all be classified as characters from the Wizard of Oz and I've formulated a hypothesis that any story involving a team needs the following characters at its core:

• The Scarecrow (a.k.a. The Brain) - The genius character who is pivotal to following the clues the villains leave behind to figure out the master plan and how to stop it.  They're often a little clumsy and fall apart easily under stress.  Examples: Willow (Buffy), Topher (Dollhouse), Simon (Firefly), Bruce Banner and Tony Stark  (The Avengers).
• The Tin Man (a.k.a. The Heart) - The character that keeps the team sticking together when things start tearing them apart.  They may seem unemotional at times, but at their core they are more passionate than all the other characters.  Examples: Xander (Buffy), Paul and Echo (Dollhouse), Kaylee (Firefly), Captain America (The Avengers).
• The Cowardly Lion (a.k.a. The Courage) - This character is never afraid to get into the thick of things in order to help save the team.  Usually ends up giving courage to the other characters through their actions.  Especially susceptible to becoming a noble sacrifice.  Examples: Angel and eventually Spike (Buffy), any of the dolls (Dollhouse), Mal, Zoe, and Jayne (Firefly), the entire team (The Avengers).
• Dorothy (a.k.a. The Girl) - This is the strong female character that just wants to get back to a normal life, but isn't afraid to do what needs to be done.  Examples: Buffy (Buffy), Echo (Dollhouse), Inara (Firefly), Black Widow (The Avengers).
• Toto (a.k.a. The Mouth) - This character's only purpose seems to be to generate one-liners.  Examples: Xander (Buffy), Topher (Dollhouse), Wash (Firefly), Tony Stark (The Avengers).
• The Wizard of Oz (a.k.a. The Mentor) - This character is older and seems like they have the team's interests in mind, but they are hiding some dark secret in their past.  Examples: Giles (Buffy), Boyd and Adelle (Dollhouse), Shepherd (Firefly), Nick Fury (The Avengers).

As evidenced by some of the examples, this isn't a 1:1 model.  One character can fill many roles and many characters can fill one role.  Also, it's not necessarily a permanent model.  That is, one of the archetypes can switch for an episode or two to give them more depth (Xander is easily the best example of this).  I think you can add other archetypes to this as well to mix things up, but you must have these elements at the core.

Non-Joss Whedon Examples:

The A-Team:

• The Brain - Hannibal
• The Heart - Murdock
• The Courage - B.A.
• The Girl - Amy the news reporter chick
• The Mouth - Face
• The Mentor - Hannibal
• The Crazy (see?  a new archetype!) - Murdock

Star Trek: TNG:

• The Brain - Data and Geordi
• The Heart - Riker and Troi
• The Courage - Worf
• The Girl - Crusher and Troi
• The Mouth - Riker
• The Mentor - Picard
• The Crazy - Barkley (I just wanted to get Dwight Schultz in again)

Naruto (first 50 episodes or so):

• The Brain - Sakura and Sasuke
• The Heart - Sakura and Naruto
• The Courage - Naruto
• The Girl - Sakura
• The Mouth - Naruto
• The Mentor - Kakashi

Naruto (rest of the series):

• The Brain - Shikamaru, Shino, Neji
• The Heart - Naruto, Rock Lee
• The Courage - Naruto, Kiba, Choji, Rock Lee
• The Girl - Sakura, Ino, Tenten, Temari, Tsunade
• The Mouth - Naruto, Kiba
• The Mentor - Kakashi, Jiraiya

Teenage Mutant Ninja Turtles

• The Brain - Donatello
• The Heart - Raphael
• The Courage - Leonardo
• The Girl - April O'Neill
• The Mouth - Michelangelo
• The Mentor - Splinter

I could go on, but I think you get the point.  I'm sure I'm stretching it in some cases, but can you think of successful/popular teams that don't fit this?