I've added these notes to the OP in this thread, as we are now testing:
Mastery: Harmony healing bonus reduced by 9%.
- Ровно полдень (Azerite Trait) damage reduced by 34%.
Developers' note: Restoration Druid has an overall package of healing, damage, and utility that is very hard to compete with in solo-healed content. Two things that stand out in particular are the efficiency of focused healing on a single target with high Mastery, and the ease of contributing DPS with very little GCD usage on Солнечный огонь.
Please note, the Ровно полдень
reduction we're testing only applies to the Restoration spec.