The main reason people stacking crit on a warrior is Enrage.
But i'm not a huge fan of that. I prefer stacking strength.
As dps i dont really care about stam or parry.
For BG: 1 critrating = 0,232% crit
So 8 crit (scaling to 24) of Aku'mai means 1,86% crit against 16 strength (Foreman/Evil). Not a very good deal in my opinion.