Only 2 things that realli come to my attention is that you need to drop some hit and gain some exp (try and make it to the soft cap for dodge). That and SoB and CotG are kind of an RP overkill, choose one but not both.
Im guessing from the glyph choices your tanking is focused around AoE?
I'd stick Guardian's Dreadstones in red sockets, and keep 30 stam in your blues. You can also gun for a Titanstone Pendant which has some nice Exp on it (trash drop, 3 dropped this week for us, literally, haha)...Seal of Ulduar from 10m XT Hard mode, Mark of the Relentless from H TotC are both great tanking rings with expertise, if you can sacrifice not having the defense rating on them.
To be perfectly honest though, if you aren't having problems holding aggro, or youre not doing hard modes where your DPS is skyrocketing over 10k and you have to be able to hold aggro on them, period, then get Expertise as you go, and definitely don't gimp your stam to do it.