Looks like fun.
Here then is a knight, of sorts:
Male Human Fighter 1 (now using 40 pb)
Str 16
Dex 10
Con 16
Int 10
Wis 16
Cha 14
HP: 13
BAB: +1
Fort Save: +5
Ref Save: +0
Will Save: +6 (+10 vs. Fear and Compulsion effects)
Skills: Diplomacy 4 (+8), Handle Animal 4 (+6), Knowledge (architecture & engineering) 1 (+1), Knowledge (geography) 1 (+1), Knowledge (history) 2 (+2), Knowledge (local) 2 (+2), Knowledge (nobility & royalty) 4 (+4), Knowledge (religion) 2 (+2), Listen 3 (+6), Ride 4 (+4), Sense Motive 4 (+7), Speak Language ([some classical language]) 1, Spot 4 (+7)
Feats: Able Learner (RoD), Cleave, Lionhearted (PotS), Iron Will, Mounted Combat, Power Attack, Ride-By Attack, Sacred Vow (BoED), Spirited Charge, True Believer (CD), Vow of Obedience (BoED).
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Notes
Abilities are 32 point buy. All feats are from the PHB except those with the following acronyms - BoED = Book of Exalted Deeds, CD = Complete Divine, RoD = Races of Destiny (all WotC); PotS = Path of the Sword (Fantasy Flight).
Reasoning / Musings
I mainly wanted to see how far one might have to go in terms of 'breaking' the PHB setup, in order to create a basically functional knight type. Well, of this sort anyway. With 12 feats (including the Fighter bonus feat), by gawsh, it's almost doable!

This is just a quick attempt; I'm pretty sure I could do better, given sufficient time and motivation. Also, guy needs a name. . .
I then realised (once again) that, if one was stuck with only core classes (including NPC classes), Aristocrat would (overall) make for a
much better knight. . . if only their BAB was good. Even so. . .

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