Have you considered the 7/21/21+2 build that seems to be the damage spec of choice amongst discerning warlocks these days?
For 21 points in Destruction, you get the best parts of the tree with hardly a point wasted. I'd say its only worth going deeper if you want to get Conflagorate, and make fire your magic school of choice.
For 7 points in Affliction, you get instant Corruption and Improved Life Tap. (I'm specced MD/Ruin at the moment and I miss instant Corruption so much).
Plus this build givs you two points left over to put where you like.
Chris
For 21 points in Destruction, you get the best parts of the tree with hardly a point wasted. I'd say its only worth going deeper if you want to get Conflagorate, and make fire your magic school of choice.
For 7 points in Affliction, you get instant Corruption and Improved Life Tap. (I'm specced MD/Ruin at the moment and I miss instant Corruption so much).
Plus this build givs you two points left over to put where you like.
Chris