So this build revolves around casting a signature spell 5 times to trigger the Arcane Dynamo passive (+75% damage to next spell) and then casting Meteor with as many other damage bonuses as possible.
+15% Glass Cannon
+20% Black Ice (Alternatively, use Conflagration for +15% to targets hit with Shock Pulse + Fire Bolts rune)
+75% Arcane Dynamo
+15% Frost Nova + Bone Chill rune
+20% Slow Time + Time Warp rune
+15% Familiar + Sparkflint rune
+20% Magic Weapon - Force Weapon
Assuming the bonuses all stack additively, the total bonus comes out to +180%, almost triple damage. You won't get all the bonuses every time due to cooldowns, but as long as Arcane Dynamo is triggered, it should be hitting for over double damage. The AP cost of Meteor is high enough that in between each cast of it you should have just enough time to cast your signature spell 5 times before you've regenerated the 60 AP. If not, then sometimes you might have to cast Meteor without the Arcane Dynamo bonus or let your AP go to waste.
The only major weakness I see with this build is the lack of a single target damage spell, but you could probably swap out one of the skills for something like Ray of Frost and still keep a large damage bonus.