A few LLLLP questions

[Madsage]

You have Torment for AoE pulls, pull as many mobs as you can without risking dying or taking too much damage to reduce downtime.

Make sure to always have improved Voidwalker talent, dot up the mobs with Corruption and Curse of Agony while Voidwalker takes initial threat with Torment , have a Felhunter out if you need to silence a specific mob to pull 2 packs and then start channeling Hellfire or Rain of Fire using a /cast [@player] macro if you do not want to deal with aoe targeting.

This will deal enough damage to the mobs but you obviously can't do crazy aoe pulls like mages do (I could pull 12 mobs/3-4 packs 3 levels lower than me with mages in SM with Arcane Power cooldown every 3 minutes)

As long as you take minimal damage you can lifetap to restore mana and heal up with Prayer of Healing and continue grinding.

Things will get better for warlocks in 55+ dungeons where mobs have 14-15k hp hard hitting mobs where you can't pull more than one pack and this is where dotting and aoeing really matches mages, you can send one mob to each target and safely clear dungeons.

Affliction with Improved Voidwalker is better at early levels, SL with imp Corruption is better from 46, SL/Destro is the best late game.

Ignore Hellfire pushback talent until late game, you do not need it, focus on doing smaller packs safely if you are new to this comp, dying is a huge setback and reduces your exp/h massively, and getting low often means you have drink more again losing more time.