Apologies for asking this question, I imagine this comes up quite a bit

I had a look around to try find some minimum tank requirements but I'm afraid I didn't find it. If I'm just being blind and its in an obvious place... shoot me
My guild managed to kill Kalecgos for the first time last night and went on to poke Brutallus. But in all my time tanking, I've never encountered a fight like this and... quite frankly the amount of damage pouring out scares me.
We've got a choice of three tanks, but after having tried all three of us last night our Prot. Paladin has already stated he might be better off going Retri or sitting out this one for now as the WWS reports for our tries showed him taking a bit more than either me or the other Warrior by avoiding quite a bit less.
I'm normally a very threat-heavy person, stacking hit and expertise for almost everything and keeping avoidance as low as the healers can handle but I've put together as much armour and avoidance as I can specifically for Sunwell.
Our armoury profiles:
The World of Warcraft Armory - Zorzil
The World of Warcraft Armory - Oglaech
The World of Warcraft Armory - Quella
Is there anything glaringly wrong with how we've set ourselves up? I'm logged off in the stuff I intend to tank with, and I'm assuming Oglaech and Quella are as well.
I'm aware that the Shadowmoon Insignia isn't the best trinket choice for Brutallus' Stomps but unfortunately I can't find my Moroes' Pocket Watch. I must have vendored it by mistake at some point and not realised since I haven't used it in a very long time. I do have the Scarab of Displacement however, if that would be an acceptable substitute.
In case it also helps -
http://wowwebstats.com/2s3xqv3iiyb3e WWS reports from last night. I was the first tank on the first few tries and Quella asked to swap with me for the purposes of comparison. Oglaech was tanking on every attempt.
We still have a lot of work to do on the tactics; I laid out the absolute basics and we pulled him a few times just to see how the tanks and healers held up through the damage, which is why we ended up with tanks taking 4-5 Meteor Slashes on a couple of tries. We're intending to push for proper positioning and correct tank rotations on Tuesday (since we'd like some proper goes before the patch which changes everything just to see how we fare).