Roy Mustang from Fullmetal Alchemist: Brotherhood is famous for his confidence, ambition, and distinctive abilities, but his strongest quality may be his ability to think beyond the immediate situation. He understands that achieving a major goal requires more than individual strength. Relationships, trust, organization, and careful planning are all important parts of his approach.
Another detail that is easy to overlook is Mustang's ability to use humor strategically. His relaxed or sometimes flirtatious behavior can make him appear less serious than he really is, but this public image can also make it difficult for others to immediately understand his intentions. His personality therefore serves both as entertainment and as a useful social tool.
Mustang also represents an interesting type of ambitious character. He wants to reach a position where he can influence the world around him, but his ambitions are connected to his personal principles and responsibilities. Rather than simply wanting power for its own sake, he is concerned with what power could allow him to accomplish. This gives his ambition considerably more depth.