I saw a post saying that "Holy Shock" should be a baseline ability. I actually like this idea. Tanks can use it to pull/get aggro, Healadins can use it like a instant mini LOH, and Ret and PVP pallies can use it for an extra kick in damage. I don't think it's over powered either as it doesn't to a tremendous amount of damage or healing. It's just a versatile spell that all types of Pallies can use.
I agree that Holy Shock as a baseline ability would not be overpowered. However, I do not think it would be a good idea.
Restrictions define us. What we cannot do is as important as what we can do. And one of the fundamental restrictions for a paladin is that we do not have ranged attacks. It's a class-defining restriction.
Restrictions also breed creativity. Paladins need to learn to body-pull, to fight multiple enemies at once, to use Judgement of Justice effectively. I find that paladins are very sensitive to the aggro radius of mobs. Because we cannot pull, we play very differently from the other classes. A profession such as engineering is very valuable to a paladin, as is Linken's quest in Un'goro (to get the Boomerang). More so than to other classes. And this difference is good. It makes playing a paladin a unique experience.
So while a baseline Holy Shock may not be overpowered, I think it would weaken one of the major restrictions on the paladin class, leading to a less creative and unique class.