A couple things.
First, don't go for a Tal's amulet with Cold damage just because it has cold damage. When something adds "X% Damage as (insert element here)", that doesn't mean it boosts skills or weapons that also have that elemental property. What it does is it increases your total damage by X% of your "black damage", in the form of the specified element. Your "black damage" is the non-elemental damage of your weapon (base weapon damage plus non-elemental bonuses if any) plus any min/max damage on jewelry, plus the damage from your offhand. This affix on some legendary/set items (Tal's amulet, Zuni boots, Triumvirate, etc.) has no impact on what skills you use or what element those skills are. Tal's amulet is still an option, but it doesn't have to have "cold" damage to be good.
That being said, the only items that would specifically play into this sort of build are Frostburn Gauntlets and the Fragment of Destiny wand. We all know how sub-par these items are, and even with a build like yours these two items can be easily out-classed by the basic gear everyone wants: trifecta gloves and high dps+socket weapons. Tal's 4-peice also plays into your build, and could actually be pretty good with the AP regen. The problem is, you lose Witching hour, your 12% Ray crit helm, a shot at an amazing Mara's, and it's likely Zuni Marrow is a better armor for you than Tal's (see below). Overall, it seems like a loss (as usual for Tal's set bonuses).
On the other hand, Mara's and/or Skull Grasp with Ray bonus could do well for you, but if you're intent on no IAS, you might want to forego the Skull Grasp. Another suggestion for you is Zuni's Marrow. Tal's Armor is great but it has IAS, and with your Zuni boots the Marrow would give about the same dps because of the +130 more INT, plus better survivability from the AR.
You look like you could use more AR and armor overall, actually. Look for INT, Crit, AR, Armor, vit rare bracers (INT, crit and 1 other of those stats will beat what you have now) and possibly AR or armor on your boots, gloves and even helm (or APoC). A Mara's plays well into this too with its natural Vit and AR. Your amulet is good, but as you've already stated you can get up to 17% Ray crit on a Mara's, plus INT, Vit, AR, STR (armor) and 2 more random rolls. Finally, a Zuni Pox with CC would be just awesome if you also got the Marrow- INT, CC, CD and double rolls of AR? Awesome. (Your rare ring is pretty awesome too. Might save this one for last.)
Do you really have Frost Nova "always up"? Seems a little too good to be true even with your very high crit chance on Ray, mostly due to your low APS (there's that IAS deficiency again). I don't know how well you take hits with this setup, but you could consider the Prism rune for Diamond Skin, and adding EB in the place of Frost Nova.
The biggest gain here is that EB doesn't force a casting animation and Frost Nova does, so you would no longer be interrupting your Ray channeling. Re-casting Ray costs more AP than channeling it, so even though you're spending AP on EB, you're netting some back from a lessened cost of Ray and switching to the Prism rune. Plus EB has a decent coefficient and should trigger some CM and APoC procs too. (This could get even better if you found a helm with APoC. Another thing this can do is give you more options for a good Mara's in that you can consider EB Mara's as well as RoF.)
You could argue that Frost Nova adds damage too through Bone Chill, but that's only during Nova's duration. If you get some pretty decent up-time on Nova then the damage comparison to EB may come out as a draw, but still, EB doesn't interrupt Ray, and Nova does. This is highly dependent on your up-time of Nova though, and whether you can still survive without that CC.
You could try getting Evocation over Glass Cannon. You'd get some additional up-time on DS-Prism so your spells stay low and you'd get more EB casts for additional damage, plus the survivability "boost" of not taking a 10% penalty to damage reduction. It'd be a net dps loss though.
All of this is just my thoughts and suggestions of course. I've considered a build almost identical to this myself (with all the variations I've talked about here) but never got around to trying it out. In the end, just go with whatever is the most fun. This is a game after all.
Edited by SeravokX, 15 January 2013 - 05:15 PM.