My main focus for balance is PvP. As I understand it Ret happens to do quite well in Raid and has a pretty solid hold on being top tier in M±. TWW talents seem to help it even more so in M+.
For PVP, a few issues will arise in nearly all PvP encounters.
Some of these can remain but having all possible in the same match feels bad.
Rets off healing and self healing is so low I’m not sure it can be considered a hybrid for PVP.
4-5min defensives that if allowed to remain last 8 seconds, but usually are removed early by 2 seconds casts, sometimes by 1 min CD dispells.
Those dispelled defensives still applied Forbearance so enjoy your added vulnerability for up to 28 seconds while up to 3 other defensives cannot be used on you.
Lacking tools most melee have is apparent and a large hindrance to success while still doing less damage at range than in melee range, and less damage than a lot of specs if you were to be ignored. Ret cannot possibly bring to the group:
Disarm
Lust
Instant mobility
MS effect
Spammable CC or multiple instant cast CCs that won’t break from damage
Effective self healing from doing damage
Fall protection outside of Bubble or BoP which are required to use to live for a bit fighting almost anyone
Blessing of Spellwarding protects who has it active from exactly 0 magical CCs
Blessing of Freedom is dispellable and stealable with Blessing of Spellwarding active so mobility is slower than normal running speed during most combat instances.
Invisibility.
There’s not necessarily a thematic reason for Ret to gain most of the above tools it lacks, but neutering it’s healing, armor, AND damage was made worse due to it’s tool kit having these gaps, and it is also one of the most visually telegraphed specs. Countering what a Ret is doing effectively requires no add ons or weak auras. You just know what you have to do to prevent what Ret is doing because your eyes are open.
Since it’s tier set for two consecutive seasons revolved around buffing DoTs that are dispelled in PVP, Ret hasn’t been in the best place. Ret has nearly all offensive abilities and PvP talents and defensive and healing talents nerfed in PVP so seeing a Ret crushing the meter in M± doesn’t translate to good damage or survivability in PvP.
When Ret, with all of the other weaknesses were still present, was tuned to do threatening damage, I was happy, that lasted 3 days. Recently I stopped being stubborn and rerolled to MM hunter and my BG and Blitz experience greatly improved, and long time hunters swear MM is terribly designed and need a total rework. If MM is garbage and needs a rework like the Hunter thread suggests, but it is leagues above Ret for a good portion of the PVP content, Rets gotten a pretty bad rework/follow up tuning.
On the positive side, TWW looks great for Ret. Lots of specs got new cool additions to their kit, instead Ret got, more damage including more cleave and AoE. Unfortunately if they leave Ret overtuned it won’t be intentional to counter it’s weaknesses, and will be responded to with unreasonably harsh nerfs since Ret isn’t allowed to be a strong contender.