In 3rd Edition, according to many people, fighters suck at high levels. I don't know that from personal experience, but when it came up during the Pathfinder RPG Playtest, I came up with the idea of having, not just one fighter class, but several. Here are a few of my ideas.
Warrior: A basic, no nonsense fighter. Does not rely on fancy tricks, but simple, time tested techniques. Can call upon inner reserves of strength that give him an edge on the common fighter.
Soldier: Obviously most suited for the battlefield, but also useful in normal campaigns because they're abilities allow them to do well in adventuring groups.
Cavalier: The honorable fighter, often noble born. Probably based heavily off of the new Pathfinder class.
Duelist: These fighters pursue battle with a passion few others can match. Basically a "Kensai" class, but less culturally specific.
Hunter: A guy who hunts, but might be a murderous assassin or a heroic monster slayer. Generally based around taking down an opponent quickly and efficiently, and trying to stack the odds in his favor before battle begins.
I'm not sure what I'm doing with the paladin, barbarian and ranger. If I do retain them they'll likely be 90% identical to the versions in Pathfinder. The ranger kind of overlaps with the hunter, but if I make the ranger more specialized there might be room for both. It might instead be a prestige class, and paladin may also recieve that fate. Barbarian may also be a variant of warrior.
I've also considered changes to non-fighting man classes as a result of this idea. I'll discuss that in later posts.