Why don't Paladins have any unique "Cures"

[Alukah]

snip

THM trait - Magick and Mend II - Increases base action damage and HP restoration by 30% and allows for the stacking of a third Astral Fire or Umbral Ice.

ACN trait - Maim and Mend II - Increases base action damage and HP restoration by 30%.

And BLM/SMN have higher magic damage than PLD (obviously) so their heal will naturally be higher.

So you have an actual healer healing for over 1k, caster DPS healing for ~400 hp and PLD healing for 200-250 HP.