I think you have the right of it, DrunkonDuty.
I just experiment, seeing if I can - in general - create characters from films and books using the feats and skills presented.
It's just for the heck of it, really.
I remember the cavalier from 1E. He was a pretty capable fellow.
Let's see if I can build a competent cavalier here (say, 10th level, something akin to what we sometimes see in the books.) Forget the limits on feats: let's just give this guy all the appropriate feats for a really skilled cavalier.
My take?
Let's start with the Player's Handbook.
He's got the fighter feats of Armor Proficiency Light, Armor Proficiency Medium, Armor Proficiency Heavy, Shield Proficiency, Simple Weapon Proficency, and Martial Weapon Proficiency (3E assumes fighters have MWP, so the cavalier would have it also.)
Now, what else would he have? I would grant him Alertness. If he has no squire, he must put his own armor on (somehow), and he must sense danger in time to react. No squire is going to do the fighting for him, while he dons his armor (as I have heard sometimes happened historically.)
I'd give him Combat Reflexes. He is a skilled fighter, well trained and able to take advantage of unready opponents. It is not always a matter of dishonor to make Attacks of Opportunity (such as, at cowardly knaves fleeing from honest combat, or the cowardly bowman attempting to shoot at him.)
I'd give him Dodge. It represents fighter training, skills, and instincts that have been honed finely in battle. (Mobility is iffy. He might have it. He would not have Spring Attack, since that is dishonorable.)
I'd give him Great Fortitude. Cavalier training is grueling. Marching, riding, and fighting in armor is grueling. And this person is supposed to be really good at these things, something really special. (He's no match for the Big, Bad, Barbarian in fortitude, but he is still hardy.)
I'd give him Improved Initiative. He has run into too many cowardly knaves, rogues, and wizards. He knows he must act quickly, and has intensively practiced quick reactions and decision-making.
I'd give him Leadership. He is a cavalier, and he aspires to the Nobility of the Realm.
I'd give him Mounted Combat. This is to faciliate other feats in this chain.
He also has Trample, Ride-By Attack, and Spirited Charge. (But not Mounted Archery, ala the Rohirrim. He is Man of Honor, and desires above all to give his opponents hand to hand combat.)
He has Power Attack, Cleave, and Great Cleave, as a person who specializes in melee combat. (He does not have Sunder: he expects an opponent to surrender and drop their weapons, or fight the good fight. He does not have Bull Rush or Improved Bull Rush - he's a warrior on horseback, not a charging Barbarian!)
He has Quick Draw. He has mastered the art of getting his long sword out of that sheath in an instant, or readying his lance quickly.
He has Skill Focus - Riding. (and possibly other skills.)
He has Toughness (once.) This is a hardy fellow (as per the 1E Unearthed Arcana.)
Has a look in the Complete Warrior
I'd give him Close Quarters Fighting. Enemies will have previously tried grappling, and this fellow is an expert in hand to hand combat. (Indeed, that's what he wants above all else, is honorable hand to hand combat - he sneers at grappling, and has prepared himself against those who would do so.)
I'd give him Eyes in the Back of your Head. He is stuck wearing a helm. Always has been. He needs this feat to counter the blindness helms confer.
I'd give him Hold the Line. He is an expert against those charging Barbarians, a bulwark of defense for his side.
If the cavalier has a long history of protecting friends, I'd give him Improve Combat Expertise: he has had to fight retreating battles against superior opponents, while his downed friends were carried off the battlefield.
If - and only if - the cavalier was a real shield prodigy, I'd give him Improved Shield Bash, Shield Charge, and Shield Slam.
Looks in the Complete Adventurer
I'd give our cavalier Combat Intuition. He has learned to anticipate the foe's moves (and the hidden motives of knavish, dishonorable opponents.)
I'd also give him Danger Sense. Again, he's been attacked in the night by rogues and knaves and monsters, and has no squire to protect him.
He is a leader, this cavalier, an inspiration, and so he has Expert Tactician.
Were he a cavalier-paladin, he'd have Force of Personality (he's not, though.)
He has Hear the Unseen. Another effort to compensate for the blinding effects of wearing a helm.
If he is VERY EXCEPTIONAL, he has Quick Reconnoiter. But if he has this, he's up there with D'Artagnon, in terms of competence. He's one guy you don't want to mess around with - he's just too good.
So this 10th level cavalier has the Fighter Starting Feats, plus:
Alertness, Combat Reflexes, Dodge, Great Fortitude, Improved Initiative, Leadership, Mounted Combat, Trample, Ride-By Attack, Spirited Charge, Power Attack, Cleave, Great Cleave, Quick Draw, Skill Focus - Riding, Skill Focus - Long Sword, Skill Focus - Lance, Weapon Specialization - Long Sword, Weapon Specialization - Lance, Toughness, Close Quarters Fighting, Eyes in the Back of Your Head, Hold the Line, Improved Combat Expertise, Improved Shield Bash, Shield Charge, Shield Slam, Combat Intuition, Danger Sense, Expert Tactician, and possibly Quick Reconnoiter.
