1) I choose to not participate in a hardcore raiding guild and I run with PuG's, instead. They won't let you roll on anything but plate/str items, and there's a reason why. I don't have access to all the items because of this so your reasons for picking agi over str might not apply to some people, me included.
2) You look awful in non-plate (granted our t10 is ugly, anyways) and my eyes hurt when mouse-overing agi-gear with str-gems.
3)I bet your guild's rogues and ferals are freezing in iceold icecrown
All their clothing was mindlessly given to Rets and Furys..
4) No seriously, gratz and everything to you, but that's not everyones cup of tea. I'd assume the OP has access to endgame gear, too, judging from his armory, so your tips might apply for him, though I think he's overdoing it agi-wise. Guess RAWR could be of more help here.