First thing first, CodenameG, great CC. This is probably the best mage CC I have used yet. I have no complaints.
That said, I am currently in the 30's leveling as frost. I have seen a couple of things that can be changed/implemented/improved.
First, it's been mentioned before, the use of frost nova needs to have a health check or range check early on in the rotation. It tends to do it when the mob has low health.
Next, I have only frost bolt checked as a puller. It does pull with frost bolt about 50-60% of the time. The other times it pulls with arcane missiles. Which for the most part is fine, but on a melee mob, it allows them to reach me faster.
Finally, when it does cast frost nova it jumps to the left. It tends to look botish. It would better if it jumped randomly back, left or right, or even have an option to step backwards a few steps out of melee range instead of the jump.
If you get to these, great. If not, it's not a big deal. Just wanted to add my two cents.
Definite kudos on a great job!