Sacred shield is a crutch for Ret in PVP. It's too overpowered when used in combination with Resil. gear.
Lay on hands while not usable in Arena is still way better than anything any other class has for PVP. Making it usable only on other players won't hurt Holy all that much since they mainly use it on other people anyway.
With that being said i think they should go one or two steps further with these changes.
Make LOH a talent choice. Change the IMP LOH talent in the holy tree to be the spell. Put the Improved version down the talent tree further somewhere around the 40 pt range.
Keep Divine Guardian the same and put a linked talent deeper in Prot to increase the amount of damage absorbed by SS to 120%-150% of Spell power.
Finally, Remove the healing buffs from Touched by the light and Sheath of light. Protection and Ret paladin already have access to baseline healing spells. There is no need to augment them for non healers.
If you want better healing abilities. Dual spec.