The spec is being set up for a second Battle for Azeroth regarding reliance on external procs to do damage.
If under the effects of Fodder to the Flame, Metamorphosis and Furious Gaze you end up at 58% haste without any equipped items (assuming the correct time of day for Night Elves or playing Blood Elves, since Touch of Elune grants 1% haste at night).
Add Bloodlust to that and you end up at 105,6% haste. No items. The haste soft cap of 100% is reached and exceeded, greatly lowering the value of haste.
You are most likely not going to end up without a single item granting you haste, and other covenants also can grant haste through soulbinds - Hammer of Genesis of Forgelite Prime Mikanikos, Kyrian; Thrill Seeker of Nadija the Mistblade, Venthyr; or being granted haste through a proc of a friendly healer’s Niya’s Herbs, Night Fae.
This is exacerbated by the redesigned Cycle of Hatred, which introduces a positive feedback loop to the spec - Eye Beam grants you haste through Furious Gaze (and even more haste if using Demonic), and more haste (up to 100%) lets you cast Chaos Strikes faster to reduce the cooldown of Eye Beam to cast it again. Blind Fury helps in this regard since it effectively grants you almost 4 free Chaos Strikes (due to the refunds, the effective cost is 32 fury without any enhancing effects) after casting Eye Beam.
To make things worse, a legendary that can instantly reset Eye Beam’s cooldown exists.
It gets even crazier if we reach the haste that makes Demon Blades take off towards near-infinite fury, as it is the only source of fury that infinitely scales with haste.
The reason it is bad is it makes haste the third bad secondary stat, following mastery and crit. Versatility will be king once more.
The spec needs reasons to use other secondary stats instead of getting an aura buff after an aura buff and having to rely on external sources of power due to the inbuilt tools being pitifully weak.
Baseline Eye Beam suppresses haste and crit.
Due to how strong First Blood is, it makes mastery sort of a joke when used - it however competes with Cycle of Hatred which might mean it does not get picked.
Please remove the absurd amounts of haste from the base toolkit and instead introduce scaling that might also serve as tuning knobs.
A couple of suggestions:
Chaos Strike could refund fury on crit as it used to be in Legion. To reduce the feeling of feast or famine, have each strike crit separately and refund a lower amount of fury. Have Chaos Strike rank 2 increase the refund by a bit, and Chaos Strike rank 3 to increase crit chance by 10% instead of increasing damage.
If the above is applied, have Annihilation increase crit chance by 30% instead of increasing damage. If that’s not enough to tune crit to reasonable levels, add a crit damage bonus.
Have Death Sweep (and perhaps Throw Glaive) deal Chaos damage during Meta, but do not modify the damage formula (to keep the baseline damage of DS similar, but have another way to boost the value of mastery).
Remove the haste suppression of Vengeful Retreat when talenting Momentum - perhaps make the CD scale with haste? Or to stop mobility from becoming overwhelming, have haste increase the fury generation?
Furious Gaze needs to die in a fire. Demonic should last 8 seconds, but could disable the Metamorphosis invocation if talented?
The Eye Beam/Blade Dance cooldown reset when invoking Metamorphosis should also die - as much as I hate the word, it feels clunky due to completely forcing you into a set course of action while Legion Meta was pretty liberal in its use, which was pretty important due to the extremely long cooldown.