Like many others here, I'd say it's dependant on the deity. Some deities are more Lawful than they are Good (Cuthbert), while others are more Good than they are Lawful (Pelor); as such, I would expect their Paladins to have similar leanings.
My own take on the matter is to go with Paladin Prestige Classes rather than a single Core Class; Each Prestige Class is then geared towards the faith they come to represent. This, consequently, allows for Holy Generals that are LN Paladins of War Deities, Holy Beasts that are NE Paladins of Murder/Hunting Deities, etc. Of course, we don't use the term "Paladin" except for one religion (being a Lawful Good religion of Honor, Courage, and Rulership), of which it (along with the others) are simply entitled "Divine Champions". This allows PCs to be drawn towards the champion-type with the behavioral expectations that most appeals to them.
To date, the only taker thus far has been for a Neutral Good faith of Mercy, Repentance, and Enlightenment; the character was thus bound to a code that enforced capture over slaughter, redemption over punishment, and re-education over execution. Not that slaughter, punishment or execution were forbidden, but foes that have been captured or have surrendered usually had options available other than the chopping block.