At any rate, merging Oblation with either Dark Mind or TBN would prevent button bloat in the future, so whichever one they go for is going to be a net positive either way.
The only thing I'll comment on here is that you see the bonus of Dark Mind as early as the chrysalis because its tankbusters are magic damage.
You handled the Delirium, Living Shadow, and merging of defensive cooldowns, nothing needs to be said on my part for those. The rest I'm just going to put my combine with my input for an updated list of suggestions for the dev team.
Either perform ItsUrBoi's suggestion for Carve and Spit/Abyssal Drain, or merge them into a strong aoe on the GCD with a 30s or 60s cooldown to further prevent button bloat issues for the future.
Again, referencing the post above mine, add some form of minor sustain. Let Edge/Flood heal you with Dark Arts or revamp Blood Price to for percentage based healing based on the damage you took, or allow it to pool damage you take until it hits a certain threshold and then it heals you for that amount.
Do something with salted earth, Salt and Darkness was an attempt but feels more like a wasted opportunity since it feels like just another oGCD we need to press.
Another GCD for us to spend gauge on a cooldown, whether that's placed into the Delirium combo abilities as we have suggested or otherwise.
Have some interaction with the darkside timer in itself or just make Darkside a passive. (a couple Delirium changes we suggested a few times would remedy this)