This thread is a perfect example of what goes wrong. A person posts their ideas on the topic of dark knight's tool kit which i also agree needs adjustments but then turns into a pointless debate on 100 potency this, 1200 mp that.
I feel the skills need function adjustments first and foremost, the numbers should be worked out secondarily.
Part 1:
it would be interesting to try the OPs idea here, however i must comment on aoe skills.
Personally i dont like having unleash and abyssal both spam able at high levels.
i would like to see DRK get a trait the level abyssal is earned that turns unleash into an oGCD that once used is morphed into a one time use of Scourge that absorbs hp with dmg dealt.
Part 2:
agree on sole survival needs to be more useful.
regarding the connection between Delirium, blood weapon and price.
i would like to see Delirium become a weapon skill again that is oGCD and adds lower amounts of mp and slightly extend time to blood weapon and price so that it may be used way more often(almost spam able) so you are "fighting" to keep the buffs going longer.
Part 3:
agree with all mentioned here
Part 4:
I really like the shadow wall idea here.
I like dark mind getting the option treatment the way shadow wall did but perhaps something different with the Dark Arts version only because its almost too similar to the other tanks. What if it made the magic damage taken be shared evenly with nearby party members. or for the party buff take, makes magic dmg received by nearby party members become a dot instead burst for the duration.
The Blackest Night:
Could use adjustment not sure what is mentioned is it though.
with the changes mentioned it appears DRKs would be over filled with mp and while reading this thread earlier it is mentioned that we could be safe adding another skill.
Soul Enslavement: a oGCD ability. drains mp while active, the way Darkside used to but at a faster rate. while this is active souleater can be used with full effect without combos. or something on that idea that is balanced