Blizzard have posted the details of the healing changes coming with patch 10.2, which is on the PTR now. The changes come in the form of nerfs to mana regeneration abilities, AoE healing and raid cooldowns, as explained below. For specific number you can check out the full 10.2 PTR notes here.
Healing Updates (Source)
Healers have a lot of decisions and resources to manage that change depending on the type of content you are doing. At its core, we want healers to have interesting abilities and choices to make while healing, and we want you to have to manage your mana pool. We’re hoping our changes reduce the amount of overhealing and make mana matter slightly more, which should make healing across the game a more enjoyable experience.
Single target healing spells currently don’t feel like they move the health bar enough. We want these heals to be impactful and have a purpose, and hope this makes healing a Mythic+ dungeon less stressful for healers.
Group healing spells have seen a lot of modifications and increases to their total throughput over the course of Dragonflight. These spells often feel like they are rapidly increasing a raid from a damaged state to a full health state. We plan on adjusting the effectiveness of many of these spells.
Raid survivability cooldowns feel like they have all entered the territory of making your raid feel nearly invulnerable when being used. While it’s a great moment for everyone to stack in a Power Word: Barrier and reduce damage taken and stack a few healing cooldowns, we think the combined power of these has escalated to a point where they make the raid slightly too sturdy.
Mana generation is a problem that’s related to all of the above. We want mana to feel like a finite resource and for the few ways you can still generate mana to be relevant, but want your spell choices during a raid fight to matter. We’re reducing the effectiveness of many mana restoration class abilities and specific items.
Please test healing in the Guardians of the Dream PTR and use this thread for any general feedback you have about it.
Thank you!