For gemming gem all stamina unless the slot bonus is 9 stamina or higher in which case put in a 15 stam hybrid gem. If you use Rawr make sure you use Burst mode since that is the most realistic of all of the options, keep in mind that Rawr doens't take in unavoidable damage valuing stamina even higher.
For your enchants get the pvp enchant for your shoulders and 18 stamina to your gloves. An easy upgrade for your trinket is the Glyph of Indomitability. For multi-mob tanking charge in, use Thunder Clap right when I get in, use Heroic Throw and Shield Bash to silence the casters and at that point I use Shockwave followed by Thunder Clap and when those two abilitys are on cd I spam cleave and tab target with single target abilitys.