Blood Weapon / other DRK suggestions:

[JackFross]

As for DA-CnS: Sure, I can reserve it to use with DA. Provided I don't have to redirect too much mana into defensive CDs, because I have the habit of rotating them, so I almost always have grit + some CD going.

DA defensive cooldowns aren't things you just use because it's a cooldown and you want mitigation. You're supposed to time those properly so that they DON'T become a drain on your mana. And there's only two defensive cooldowns that eat Mana, anyway, and neither of them tend to be super useful in single-target fights outside of specific instances in raids for DA+DM.

Using CnS without buff on single target is also absolutely fine, if you sit in Grit or no, because of reasons, that may happen.
CnS has mana recover and it shoudn't be discarded, or said that starving for mana was played wrong as DRK. i am always around 40%-20% mana after dropping grit between Blood Weapon cooldowns. And I know how to DRK, trust me. :P

It can absolutely be said that if you're starved for Mana at the 60s mark when CaS comes off cooldown (or at the 30s mark when Dark Passenger is back), you mismanaged your Mana. Like. That's exactly what it means. In a single-target situation, as I just mentioned, your Mana is only used to DA a Souleater or to shoot off Dark Passenger and DA+CaS. If you're lacking for the latter two, you wasted too much on the former one. I say wasted, because DA+SE is the least efficient use of Mana and should only be used when you'll otherwise hit maximum, or when you'll still have enough for the next DP / DA+CaS if they're about to come off cooldown.

Any time you're using CaS for Mana in a single-target encounter, you overextended your Mana reserves. It happens to the best Dark Knights, but that doesn't mean it's "fine" when considering how to play the class optimally.

On a PvE aspect, I think the skill is just lackluster compared to it's comparables

Thoughts?

This whole discussion is super fair. You bring up a lot of good points I hadn't really thought about. Sure, you can play it assuming you have SoSu, but you can also play it just fine without even ever having the skill. And that's where you guys are all seeing an issue. Sorry for being such a blockhead. D:

That said, not sure about the dot drain - it sounds similar to Circle of Scorn, but I like that idea. Something you can only activate when you're at low health which gives you some sort of regen effect. A DoT drain, heals when you take damage (like BP for Health), or even just a flat regen effect on yourself. It'd synergize well with Living Dead in any of these scenarios, and would overall be a better addition to the kit, for sure.