"Can't downrank your hellfire, so you blow a few thousand mana to stay in combat, and then find out it was a druid >.<"
Well, I have to disagree with you here, since you can see if it is a druid, by the buffs :] if you didn't know
"no offense, but my rogue doesn't even bother sapping warlocks, because they're usually so squishy"
Yes, warlocks can be hard to sap, but you can sprint + distract + sap, and go on the priest, if you play vs lock/priest.