Currently I eather missed it or there is just no point in the subclasses for warlock right now. What does the The Great Old One get?
The big one is Dissonant Whispers which is a really stronk 1st level spell that does Psychic damages and frightens the target on failed save. Nobody else will get that until they release Bard.
Other stuff is down the road.
Of course we are still missing The Archfey subclass. But they did promise to provide it.
