There is only one Tier set Bonus change in this build which is to Holy Priest!
Prayer of Healing increases the healing done by your next Flash Heal Binding Heal Binding Heal <brHeal or Heal by 60%. Item Set: Gilded Seraph's Raiment: 2 pieces Your Flash Heal Binding Heal Binding Heal <brHeal or Heal spells increase the healing amount of your next Prayer of Healing spell by 30%. Read more on wowhead.com