Contemplating the Martial Art abilities of the fighter, since I see the fighter as a Martial Artist, I took a stronger look at the Pathfinder Fighter. One thing is for sure, a Fighter is a student of the Artes de Mars, those techniques which would improve on hitting your opponent.
Random 4e Supporter: "Ah, but the fighter gets only one basic attack."
I'm proving you wrong. That's why I'm developing Martial Arts rules for the Fighter in the field. These martial arts appear as Weapon Arts, the art of using the sword, staff, hauberk, pitchfork, war flail, and other weapons to better get your opponent and to defend yourself. I've chosen to develop three core arts tht are still alive (one is technically resurrected) from two different cultures and then to expand from there.
Medieval Swordsmanship: Medieval Swordsmanship is the base that all fighters learn. On the Academy of Medieval European Arts web page, Medieval Swordsmanship is combat skills. Some of the skills include: Grappling (that's Wrestling to you), Archery, Longsword, Dagger, Arming Sword (broadsword), Poleaxe, Spear, Armored Combat, sword and buckler (sword and shield), and Mounted Combat.
Base Attack: That one basic attack some 4th Ed players complain about.
Parry: The art of blocking your opponent's blade with your blade.
Half-swording: The art of using your sword as a club by holding the blade.
Tai Chi Jian: Another living sword art. This is the sword art that the flashy fights you see in Hero and Crouching Tiger Hidden Dragon is based on. It's a living art that is taught as part of Tai Chi Quan; thus its a part of Tai Chi. The fighter specializing in Tai Chi Jian must learn Tai Chi Quan first. A master of Tai Chi Jian can reach harmony with the Laws of the Universe and master them. It is an elegant style.
Base Attack: Yet again, that one basic attack.
Parry: Parry yet again.
Renaissance Arte of Defence: The final one to build on is the Renaissance Arte of Defence. Mostly practiced with the rapier, sabre, or foil, its as elegant as Tai Chi Jian. The Arte of Defence is often showcased in movies like The Princess Bride. Again, its about defending yourself. Unlike Medieval Swordsmanship, the fencer often trained with one weapon (and used guns instead of the other arts).
What I am proposing is to change the fighter into a general martial art stylist, and make the duelist PrC a Prestige Class specializing in mastery of one particular Weapon Art. Fortunately, the Pathfinder version allows one to do that. In Rolemaster this is a lot easier than it looks with the Martial Arts Companion, in d20 -- what ever the version -- its a lot harder than it looks because 4th ed and Pathfinder doesn't give you a lot of options.