for the most part, i can't complain too much about these guys. they do their job and do it fairly well. however my one criticism is that they have to be lawful good. seriously? only the most law-abiding and pious of individuals may become zealous champions of faith? seems a tad shaky to me, which is why i almost always allow people to use the variant paladins of freedom (chaotic good), slaughter (chaotic evil), and tyranny (lawful evil). by and large, it really makes a lot more sense to have these iconic champions of alignments and faiths *other* than just lawful good. this way, when you're trying to make a truly black-hearted bad guy, the warrior-champion of a completely vile and abhorrent cult, you don't have to turn to...a fairly bad-tempered fighter, or hexblade.
although, those could be cool too. indeed, one of my favorite combinations is to give one of the evil paladins a few levels of hexblade - mostly so one can obtain arcane resistance - meaning that you get to add your charisma modifier to saves twice. that's pretty sweet-ass considering that the paladin already has solid saves. oh, and if i may be so bold, be sure to check out the compete champion, because it's got some fairly sweet paladin-themed feats. there's one called battlecaster, and to be frank, i think that anyone who doesn't take it is a right fool. yes, it literally reorganizes the way that paladins act and behave in battle. well, not that monumentally, but it actually gives a second life to their admittedly meager spell ability.
also, in my games, much like the cleric, paladins lose their turn undead ability, as it is now replaced with channel energy. this may be partially problematic, since most paladin-themed feats rely on turn undead attempts, but i find that if they now run on channel energy attempts, it works fairly smoothly. oh, also, a paladin channels energy as a cleric of three levels lower would. to learn more about channeling energy, just click here.
you'll note that, similar to my post on monks, i organized the paladin orders along the traditional forgotten realms divisions. as i've said before, you don't need to do the same, and yes, they're forgotten realms (trademark and copyright NOT mine), but i sifted through the appropriate materials to uncover the following. it is interesting to note that, in the forgotten realms, you must chose a knightly order, from which your character belongs, but as i said there's a fair deal of flexibility with this:
An order founded in the lands south of Tethyr and recognized by the crown, they are highly respected by local humans and halflings alike. Their unique lifestyle affords them the ability to multi-class as clerics, fighters or rogues.
Companions of the Noble Heart
The Companions are the aggressive counterparts to the passive clerics of Illmater, deity of suffering. They are tasked with protecting their clerical counterparts, but also eliminating the cruel and those who are known to enjoy the torture and suffering of others. The church of Loviatar is their greatest enemy. They may multi-class as fighters.
Hammers of Moradin
These stout and stalwart dwarves are tasked by Moradin with protecting the vast dwarven realms from all manner of terror and underdark horror. Due to the danger involved, they may multi-class as clerics or fighters.
Knights of the Eternal Order
This is a recently-created order, founded by the newly-ascended god of death, Kelemvor. They are tasked to seek out all undead, but especially loathe powerful undead that tax balance between life and death, but also exist as a mockery of natural death. They may multi-class as clerics.
Knights of Merciful Judgment
This order focuses on the heart of Tyr’s philosophy, punishing criminals and law-breakers, but also being mindful of the compassionate nature of justice. They have a zeal for battling evil, extra-planar outsiders, such as devils and demons. Paladins of this order may freely multi-class as fighters, knights and clerics.
Order of the Aster
The paladins of the Morninglord are amongst the most well-known paladins across Faerun. Their tireless deeds in the service of the poor or downtrodden has made them particularly well-respected and loved across the realms. They may multi-class as clerics without penalty.
Order of the Golden Lion
Paladins within this Order may freely multi-class in a single other class, but this cannot overtake their paladin training. They are widely seen as paragons of loyalty and truth, in the service of the god of duty, Torm.
Order of the Most Radiant Heart
This paladin order is in the service of the ever-vigilant god Helm, who allows his paladins to freely multi-class as fighters, knights and clerics.
Order of the Red Falcon
A fledgling order of paladins who old the goddess of tactics, the Red Knight, as their patron. This small order has a history of triumphing in the face of overwhelming odds. They train officers and others in tactics and military history. They may multi-class as fighters or knights.
Shields of the Golden Hills
Under the guidance of their gnome patron, Gaerdal Ironhand, this order is dedicated to defending gnome communities against any attackers and serving as officers and champions of larger gnome military assemblies. They may multi-class as clerics or fighters
Note that paladin-themed prestige classes do not count towards a paladin’s multi-classing limitations. If an Order lists Cleric as a choice for multi-classing, the faith of the cleric has to be the same as that of the Paladin’s Deity. Finally, any Order that lists Cleric as an acceptable multi-class may also allows a Favored Soul instead.