Well i played DRK so far 61 lvl and my pld is 63 but as far as i could tell, the difference is not as drastic as it seems.

Damage seems alright, the only major flaw of a tank stance is getting small on MP but it all depends on the managament.
AOE doesnt seem like that great deal, but im looking forward to unlock quietus.
Single target damage is high enough, life drain makes up for the weaker cooldowns.
What i have noticed is DRK more challenging to play and funnier? There are some useful skills you could mix if dark arts to make up damage, some aoe, you need to make many choices and there is no dot you have to care about. just all about damage.

So whats the deal? I like the class more than PLD, its more indepth and interesting, however i do agree some abilities would love to get something to make them more useful like salty earth or blood weapon being usable during grit would be awesome.