You could use more spell damage (I know it's hard to get.)
While I'm sure you can take alot of regular players to town with your Mage, what Dark was saying is that versus a Pal or Rogue twink, and especially against a Hunter twink, you're looking at a bad time. The funny thing is the problem isn't survivability as much as damage output, even as a "glass cannon" class, the mage doesn't do the damage needed to take out enemies when they have that sort of HP at that level.
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Serpent Gloves would drop you 3 STA but give you a somewhat decent boost to +dmg, and you could use something else for boots methinks.
I admire you trying to Twink out something less easy, but by the same accord it will be more difficult for you to find the "perfect" gearset.
Also have you Considered Fire? I know Ice is the usual PVP build but that's generally when you have more than 10 points to work with. Imp Fireball, Flamethrowing, and Imp Fireblast might serve you well, especially considering you just got a Fireball upgrade at 18, but your Frostbolt is only level 14 (upgrade at 20.) As for trying to keep them at bay, Frost bolt is great but your only real challenges here are guys that can get to you regaurdless (hunters, rogues, ect.)