Helm - never use a non-stam hybrid gem. Change the gem to 10agi/15stam.
Shoulders - change the enchant to the pvp enchant (30stam/15resil) -> http://www.wowhead.com/item=44957
Cloak - change the enchant to 225 armor, http://www.wowhead.com/item=50466 is going to be a really good piece of gear for you to pick up when you can.
Chest - Change the enchant to 275 HPs
note: with the above changes I think you will still be over 536 defense, which is what you need to ensure you are non-crittable with the aforementioned shoulder enchant. If you aren't, change your shield enchant to 20 defense.
Trinkets: I would recommend getting glyph of indominability to replace that JC trinket
Boots: try and get http://www.wowhead.com/item=45560 made. They are very solid and will last you a while, if you have the money go for making http://www.wowhead.com/item=49907 however since they don't have defense these may be a bad move for now since you'd probably drop into the critical range. You also might hit that 9 stam bonus on the spiked deathdealers with a 10defense/15 stam gem
Belt: look into getting http://www.wowhead.com/item=45551 made until you can get the frost emblem belt.
Legs: when you can, get pillars of might crafted, but you're going to need more defense before you can really use those since they have zero defense on them.
Take a look at: http://www.tankingtips.com/2009/12/2...st-pick-order/ for help in deciding what you should get first for frost emblems. Yes I know it has warrior tier, but the same rules apply for pallies just assume it is pally tier although I would suggest putting corroded skeleton to #8 in that order, maybe even 5 depending on what other drops you get for shoulder/helm.