An ice spear freezing machine gun pledge build?

Is there a build for a witch that'd use Pledge of Hands as a freezing machine gun?

I was thinking like this:

1. Ice Spear spam. (IS+FasterCasting+GMP+ColdPenetration+CritGems)
2. Lots of crits in the tree. Doom Cast etc.
3. Life-based or low-life based, though without a shield I think life-based is more sane.
4. Some basic staff nodes, for blocking at least.
5. 3 auras (Haste, Clarity, Something) + Herald of Ice.

Oh, and Atziri. :-D