If you want to compare the two, you can't compare a hunters melee/grenade to just a warlocks grenade. You have to throw scorch in there too which also hits for around 170ish. The same melee that can leave low armored hunter with less than 10hp, not to mention you just need to have someone in your field of view and it auto aims the melee directly to the target. Warlocks now have two attack methods that can lower a guardians health to below 30 vs. one that can kill if thrown perfectly. That being said I've used both as a main in the past few months and will admit Nighstalker can be OP. In my opinion, the difference between the two is that it takes high skill to take the nightstalker class to the 'OP' level. (Although high skilled players can make almost any subclass 'OP') Where as you can give an average player the ability to spam firebolts, melee with a very large margin of error and occasionally two lives with double health and it can take them to to the same heights.