Smitten with the new smite
I like the mechanics and I like the flavor of a smite +effect.
The concept of a paladin being rewarded by his deity for taking the fight to the enemy fits, a holy warrior, champion of his deity, who aids his allies while dishing out god's will. You want a divine spellcaster pick up a cleric. The paladin is in the trenches both as protector and avenger.
A Smite is not every time the pally swings his sword, this is a special, focused attack graced with divine energy. Why wouldn't there be more of an effect than straight damage? The paladin calls out his foe for divine judgement. The act of smiting is sacred, a ritual, a prayer. The paladin of Bahamut, the protector, lends the Platinum dragons protection to an ally when he smites. A paladin of Pelor, the healer, mends wounds of his comrades when he invokes the Sun god's might. It fits the theme of the divine warrior much better than psuedo-Vancian prayers.