What a great topic as I've been struggling with this as well.

I'm still at low levels with my WMM (level 18 ), and I've only done ragefire chasm. And, already, I've reworked this repeatedly.

Mine looks like this:

mages: fireball
warlock: curse of agony, corruption, immolate, shadow bolt, shadow bolt, shadow bolt

I have a reset set up on the warlock. My suspicion is I'm gonna need to totally rework this as I get more talents.

I plan on going destruction warlock, but I'm still went 5/5 improved corruption and getting my +sta buff from the imp for 3/3, then I'll go into the destruct tree.

My suspicion is things will need to be totally reworked every few levels, throughout the leveling process.