Not sure how much visibility this will get in a mega-thread, but here goes.

Concerns:

1. The rotation is really repetitive and bland with just 1 DPS combo. People currently compare DRK to 2.0 PLD.

2. The class is noticeably squishier then the other tanks, especially before level 70 without TBN.

3. Unleashed is useless after Abyssal Drain.

4. Dark Passenger is hardly worth using, its very underwhelming.

5. Blood Weapon and Blood Price is unnecessary button bloat.

Solutions:

1. Bring Scourge back as a 3rd combo finisher after Syphon Strike.

Scourge is a pretty cool animation to keep around, and DRK is the only tank with 2 combos instead of 3. WAR tracks Storm's Eye and PLD tracks Goring Blade, so tracking Scourge would add some parallels. Have seen this suggested plenty.

2. Make Dark Mind reduce both physical and magical damage.

The amount reduced or the recast timer can be tuned. Could also remove the DA part to make it simpler to use/balance.
PLD got block, shelltron, bulwark, and cover extended to magical to cover their weakness while DRK got nothing, just TBN at 70.
This is also suggested plenty.

3. Either delete Unleashed and give us Abyssal Drain at level 6, or give us a trait at 56 that improves Unleashed and makes it into Abyssal Drain.

Not much to talk about here, having 2 AOE skills that do the same thing is redundant. WAR has Overpower (DPS) and PLD has Flash (enmity) and Total Eclipse (DPS).
Again, a common request.

4. Make Dark Passenger free and make the DA effect baseline.

It makes it always worth using and makes this DP easier to use to balance out the complexity of adding a 3rd combo. Dark Passenger NEEDS a buff, its not usable currently.

5. Make Blood Weapon usable in Grit, and merge the effects of Blood Price into Blood Weapon.

If you want to, you can make the Blood Price effect only happen in Grit by giving a Grit Additional Effect to Blood Weapon. As for separate timers, you could have both buffs with separate timers, similar to how WAR Vengeance gives you 2 buffs for the mitigation and the counterattack. Delirium could extend the timers of both. Maybe not a common solution, but Blood Weapon/Blood Price consolidation is something that is frequently discussed.

Another idea is to merge Anticipation into Blood Weapon to justify the Blood Price effect thematically and to increase desperately needed Physical mitigation, and delete Anticipation in favor of Bloodbath. (fits all 3 tanks thematically) and change Bloodbath to work from magical damage too.

And thats it, suddenly DRK is more refined and much more fun and its up to par with the other tanks. All that is missing is the old Delirium animation, but oh well. Wish they would delete the Souleater animation and give us that instead.