This is a product of TBC, not Vanilla.
You had to balance those set items statwise, introduce set bonuses and so forth, far too much meddling.
Aside from that, how do you handle sets like ZG / AQ 20, those get new bonuses as well?
In case you don't remember, due that Talent many Holy paladins specced deep into Prot so they won't run out of mana at the cost of healing output.
And that doesn't even fix one of the issues prot pallies had, being unable to generate threat while not holding aggro, they oom and are unable to regain mana because they don't take damage.