TLDR - classify Feral/Elemental Spirit wolves as ‘Elementals’ to get similar buff uptime.
Primordial Bond
[Passive] While you have an elemental active, your damage taken is reduced by 5%.
Triggers for each spec
Enhancement
- Earth Elemental - 5 min CD, 1 min duration
Elemental
- Earth Elemental: 5 min CD, 1 min duration
- Fire/Storm Elemental: 2.5 min CD, 20 sec duration
- Echo of the Elementals: 10 sec duration
- Modified by: Everlasting Elements: +4 sec duration on Fire/Storm, +2 sec duration on Echo
Without the added complexities of TWW S2 set bonuses that only further increase the duration difference, Elemental dramatically benefits more from this talent than Enhancement. From a quick check of M+ logs and raid logs Elemental currently has ~67% up-time of the passive compared to <3% for Enhancement. In S1 Elemental had an uptime of around 50%.
I would propose to classify Feral/Elemental Spirit wolves as ‘Elementals’ to bridge this gap in passive durability. Feral Spirits seem to have an up-time of around 50%. This would seem to be a good direction to bridge the difference in passive durability in the long-term without seasonal bonus added complications.
Elemental also has the added benefit of being able to wear a shield which on my character seems to add ~10% physical damage reduction. Given Enhancement is a melee and more likely to be hit by physical abilities perhaps additional changes can be made to improve Enhancements passive durability (e.g. passive damage reduction from Lightning Shield or Earth Shield).