He's a frost mage. Keep the sorcerer's cloak, throw on 10 haste rating to gloves. Get a set of a sorcerer's waist. Mindthrust Bracer's would be your only possible up from your current bracers but not a game changer. Personally, I'd prefer Conspirator's Slippers or Merger boots over Spidersilk and as Robert mentioned, Stillwaters Signet to replace Seal of Syl. Oh and don't forget Godfrey's Britches!
Mind you, there ins't a set way to build your mage. If you prefer hit capping through Spidersilk Drape and Lavishly Jeweled Ring, there is nothing wrong that. At the end of the day, your play style may differ entirely from other mages and so would your support. Run multiple sets be it stam/crit/haste/sp but be sure to remain hit capped in each of em.
BoA helm (Tattered Dreadmist Mask) when it becomes obtainable for you.
At the end of the day, not a bad CC mage at all. Minor ups, trinkets in the right place =P and you're hit capped. 7.5/10