Don't be discouraged by people talking trash about the warlock. We are in EA and like most of the classes, it is incomplete even up to level 4. Once it's missing features are added, it will feel much better.
I emphasized the use of EB with Hex, because it sounded like you were having issues combat-wise, and that's the best way to maintain your damage output, and will only get stronger as we surpass LV 4.
One of the coolest things about the warlock is it's versatility in building it. You get so many choices of invocations that really help you customize your character in ways other classes don't get.
Comparing early level warlock to early level ranger is pointless. Ranger has one of the strongest level 1-5's out of all the classes. Colossus slayer being bugged and occurring on full HP enemies takes that a bit over the top, but doesn't change that fact.
