Holy Mending is something up in the air as it requires testing. We don’t have any logs yet of Holy Priests exclusively using a Revitalizing Prayers PoH build. Benediction also benefits off of Holy Word Salvation as well…
Benediction being @ 15% isn’t as bad as it looks because you can talent 7 PoM bounces and the additional 15% chance not to consume a PoM talent akin to an extra free PoM bounce or more depending on if you get good RNG. You could with good RNG get 10+ bounces off a single PoM cast. So Benediction ends up proccing more often than it did before.
Benediction losses its usefulness when you don’t take the PoM talents though.