With this build, depending on you attack speed will cast 2-4 sparks (arcane orb with rune) and then a meteor just when the stack buff appears on you. You can make your meteor 50% more dangerous on big groups of monsters. Also you can use A meteor first to root large monsters and then cast sparks to kill them. And the shock pulse with the rune is good to make decent damage not only large packs, but single monsters too.
Also you have the Hydra, but if you feel not sure enough you can change it for teleport, but the enemies will be stuned enough to not needing to constantly run. And Arcane dymano to have even deadlier meteor impact
With this build, you will need +% to lightning damage, some Critical chance if you want, and %less resource. Actually on live im doing t2 easily with 110k dps and without a single point of critical damage.