Rexxar killed Admiral Proudmoore, not Thrall.
And Garrosh needs to be spared, because if it's a kill out of vengeance then the Sha would consume the person that kills Garrosh. Haven't people learned enough of the Sha by now? I thought these ideals were hammered in enough by now.
---------- Post added 2013-05-20 at 12:57 PM ----------
Yeah, killing him off is basically giving in to all the people who considered him a badly written character. I still think he has a lot of potential if he's redeemed, he could be like his father or somewhat a younger Saurfang. Brash but a very skilled fighter.
Him being the pinnacle of uncorrupted Orcs would be the perfect candidate to take it on with the Legion. For him it's personal. Nobody hates demons more than him.
Let him kill some massive demon like his father, but instead of dying in the process let Garrosh live.