lol, you're all dumb. Seriously, if you want more mitigation to pick up a keeshan's bandanna and put +15 FR on your cloak. I have this on almost all my characters right now. The +18 AR from the bandanna helps resist sheep, cs, and helps against hunter/mage burst. The total of 33 FR you get from the cloak chant and the bandanna gives around 40% fire mitigation and the 18 AR gives around 25% arcane mitigation. It's hard for a hunter to kill you when his main attack does nearly half of what it's suppose to. Now, if you play a worgen, you have +14 nature AND shadow resist. That's 20% mitigation for both, plus, you now have a decent chance at resisting fear and roots. That's 20+% mitigation in all magic schools except frost, and let's face it, how much do you really get hit by frost spells in the 19 bracket? Seriously guys, get your heads out of your asses and actually theorycraft your own gear. Just because the item makes your HP big doesn't mean its the optimal choice.
As far as the gems go, I don't think anyone should use them. Sure, the resil and stam ones could potentially help the bracket but knowing the many game-ruining assholes that play in this bracket I wouldn't be surprised if people started making excuses for using all the other types of gems as well. Imagine a hunter with 2 crit gems, seriously. Not to mention, if these become commonplace in the 19 bracket, people who aren't on this site, IE scrub BIS hunters, will catch on and start using the crit gems as well, disregarding what is actually beneficial to this community completely.
The tools to survive are right in front of you, you just have to actually use them.