To be honest, I wouldn't mind if they dropped death coil's fear effect. I fight scourge all the time, so it doesn't really matter anyhow. The fear effect sucks against mobs because they run and aggro, especially in raids. I like to use it as a last ditch "shit I'm nearly dead, quick, health!" healing move, personally, or a quick 1k damage from Shadowbolt and an immediate Death Coil following.
They don't run away. They run around in an extremely small raidus for 3 seconds. They won't aggro anything. It's much like Blind, except it doesn't last as long. Also, Deathcoil is what makes Warlocks overly viable in PvP. I don't know what you're talking about...
Sidoh: No, I completely understand a sword rogue wanting to fight a warlock more then a mage, trust me, I was one. 
But if you ever go daggers you'll see you'd rather fight mages.
Nah, I saw why mages would be better to fight with daggers before you mentioned it, but I still think there's a decent chance for failure if you miss an ambush/backstab.
