I can see where you are coming from. But I've always thought of DRK as beeing a "WAR-1" on the melee side. We should'nt really do more melee damage then WAR or for that matter the same. Because, thats what WARs do, do melee damage (and the occasional tank).
I see DRG as a "WAR-1" where the wyvern makes up for lost damage.
I see SAM as "WAR-1" where TP gain makes up for lost damage.
I see THF as "WAR-1" where SATA makes up for lost damage.
And I see DRK as "WAR-1" where magic makes up for lost damage.
I am not trying to make DRK like the "jack of all traits: RDM". I am simply trying to embrace the philosophy SE laid out 9 years ago. MP is just sitting there, why not whip out a Thunder III after a WS for a 1k MB! With todays update notes; that enemies will have weakended resistance during MB window makes this even more viable.
While you make the argument that if I want to cast more spells I should play RDM; I could easily make the same counter argument that if you want to do more melee damage you should play WAR
