I don't see why they shouldn't make Elemental Magic at least worth casting for DRK, but I agree that it won't really fix what's wrong with DRK anyway.

Some more unique or improved Dark Magic would be cool, like Tier 2 Absorbs or Curse. Maybe a job trait that allows DRK to continue to swing while casting?

And perhaps most importantly, change either Guillotine (or more preferably Insurgency) to a crit WS.