The slow start of the wizard was just killing me at first. It's also my second char (I have a 38 DH also) and I've farmed up a bunch of great items to gear up the wiz as I go.

The low damage was just awful.

Then I hit level 11. And got spectral blades which I just LOVE!

http://us.battle.net/d3/en/calculator/wizard#WeYdX!a

Now level 15 and zipping through content.