The second picture looks pretty good (battle stance), and we won't see him standing normally (the first picture is the standing stance that he won't use because he will be all the time in battle stance) so it won't look stupid
In a way, I don't like the idea of corrupted garrosh. =/ Didn't they say in the first place that Garrosh wouldn't be "corrupted" in any way?
what that was based on, is that they were clarifiying how everything garrosh does, every move he makes, is his own choice. No demons, or old god influence, no whispers in his ear by someone else, everything garrosh does comes down to his own, so by not being corrupted they mean he isn't influenced by anything in what he does, unlike say Grom, who was influenced by demons and corrupted blood.
The fact he becomes a corrupted orc by the final phase is just because he draws on the power of y'shaarj into his body, becoming the hulking mass, but not influenced by it at all.