Again, these are two incomparable spells.
Apotheosis is a personal empowerment and thus universal, it can used whether you need strong spot healing, duo or AoE (if only we had a good aoe spell lol).
Divine Hymn is a substantial raid buff for all healers, its function in m+ is to be AoE healing cooldown, but in practice, it’s a week garbage with 3 minute cooldown, that heals for much less than your average AoE Burst in 10s keys+. Its healing buff effect in dungeons is quite impractical and weak.
I don’t want either or, I want both, I want both AoE healing spell and personal empowerment, Also before Blizzard nerf our dps to the ground, Apatheosis could be used both for healing boost as well as damage boost, which felt great.
Although I don’t do raids too often, I can totally relate to your sentiment. Salvation felt amazing in raid fights as it could turn the tide of the fight. Alas, first in TWW it became a victim of Blizzard’s overall neglect of holy priest. Here I am 633 lvl holy priest and my salvation does 100k healing and has 12 minutes cooldown, Pinnacle of tuning skill from Blizzard’s devs.
Instead of fixing the spell they broke with their hero talent BS and “balancing”, they just straight deleted, total incompetence.
Yeah, I was totally fine with choice node of salvation / apatheosis. Blizzard just broke what worked fine with their crappy “hero” talents.
Oh no, I disagree that PoM is not “not very good”. It is outright undertuned trash. I spam it on cooldown during m+ (old habit from DF when it was actually decent) and it does like 3% of my total healing with all those 7 talents invested.
It is a very minor issue atm, because there are much bigger issues to address for Blizzard. You see, disc priest wasn’t meta in PTR for almost 2 weeks! They had to work really had to make it meta again, no time left to address holy priest spec that has been languishing for 6 freaking months.