Hi Thecus,
I noticed on Friday night you had to do quite a bit of juggling with your gear to try and alternate between maximising your avoidance and health pool. I'm not sure what gear progression list you have planned for yourself currently, but let me offer a few items and potential good upgrades in the slots that I think are letting you down currently.
Head Piece: Arcanum of the Stalwart Protector - AC revered
Requires 6k more rep. That's all of one heroic run in a tabbard, the AC dailies and a couple of hours spent questing in Icecrown for AC.
... Will net you +37 Stamina and +20 Defense
Neck Piece: Chained Military Gorget - 25 x Emblem of Heroism
I'd make this your next Emblem priority, it's a great piece that should last quite a while
... Will net you +5 defense, +12 stamina, +32 dodge and some +hit for improved threat.
Shoulder Piece: All looks good, and I see you've been diligent with your SoH dailies.
Chest Piece:Breastplate of the Solemn Council - WA Revered
Still requires 9k rep with WA. Not sure if you've completed all the Wyrmrest temple quests or not, but if so just ensure you get your dailies done every day (including Aces High) and put the WA tabard on as soon as you finish that last 5k AC. Again, will only take 3 or so heroic instances with the tabard on to complete - very close.
... Will net you +27 stamina, +20 defense, +56 expertise for improved threat.
Hand Piece:Heroes' Redemption Handguards - The Obsidian Sanctum, Sartharion / 60 x Emblem of Heroism
I'd make these your next target after the Emblem neck piece. You'll get 60 Emblems well before you get Kirin Tor exalted. Otherwise,
Horn-Tipped Gauntlets are an option from Gundrak as a filler.
... The T7 will net you +27 stamina, +21 strength, +43 dodge, +30 hit, -33 defense and a blue slot.
Finger Piece:Titanium Earthguard Ring - Crafted
A wonderful ring and is a major upgrade over your blue quest reward. I'd focus any gold/mats you have in getting this crafted. I can help with mats (orb, Eternal Earth, titanium) if you need. The only expense you should have will be the 4 x Dragon's Eyes (maybe 600'ish gold total).
... Will net you +38 stamina, +10 defense, +10 dodge, +17 strength all from one finger!
Trinket:I think there are two trinkets which can really help your situation.
Essence of Gossamer - (H) Azjol-Nerub, Hadronox
In all seriousness, you should run Azjol-Nerub DAILY until you get this to drop. It's a very short instance, and is also challenging so it's no Nexus snooze fest. Amazing trinket that you will ALWAYS keep.
Seal of the Pantheon - Halls of Lighning, Loken
The +65 defense in a single trinket when you've been struggling to maintain the raid minimum 540 figure should really help. What's more, it drops in normal mode so you can run the instance over and over in a single day until you get it. Each run will also net you +650 rep to your current tabard so it's not all for naught
So! Excluding the two trinkets for now as they are based on drops and lucky RNG's, the other gear is all 85 Emblems, about 15k rep and 600 or so gold away. That relatively short amount of work would net you roughly:
+165 stamina
+22 defense
+85 dodge
+ hit, expertise, armor, strength and some socket bonuses.
Get lucky with those two trinkets and you can add another:
+111 stamina
+ 65 defense
edit: Oh just noticed the BC libram. It only gives you 2.56% block rating at level 80, at a time where while being block capped is nice, it's not required. I'd probably get the Libram of Obstruction with an easy 15 badges sometime soon
Cheers,
Thoragk
, just wanted to say its great seeing you asking for advice 
