I have not been able to play the beta but i have watched many hours worth of game play. The main thing that makes me so happy about the wizard class is, you guessed it, lasers, red and blue. So i was looking for a build i could honestly just have fun with and destroy things. I would like to have both the ray of frost and the red laser beam in the build, i really do not know what else would be needed to boost those two to the most effectiveness.
Simply put i want to spam lasers and make it very effective =D
A somewhat damage focused build, obviously feel free to change things around but the base of this build is Ray of Frost runed to cost no AP making it spammable and somewhat eliminating the need for a signature assuming you aren't trying to use sigs to generate AP. Also important here is the cold blooded making the single target Ray of Frost cause itself to deal extra damage.
As for disintegrate, you wanted an extra beam so I runed convergence as Ray of Frost should always be your single target beam, may as well make your multi-target beam more multi-target!
Meteor-comet to compliment the already chosen cold blooded from Ray of Frost
Wave of Force in there for somewhat of an "oh shi-!" button if you get caught off guard by projectiles or swarmed, this is also why it's runed for reduced cost, can't have an "oh Shi-!" button and have it fail b/c you're out of AP.
Slow time compliments meteor-comet well for this build anytime that you're AoE'ing.
Obviously the sparkflint familiar is just to add to that "damage focused" build I mentioned. Most importantly this should be a fairly effective beam-happy build for you.
Note that this build assumes you have enough skill to avoid getting hit through use of wave of force and slow time.