the difference between garrosh and deathwing is that nobody really knew who deathwing was because outside of the books he had little mention.
we basically had no reason to want to fight deathwing other then "raaaawwwwwr ima dragonz gone blows up the world" wheras garrosh is slowly becoming darker and darker and tbh the lore of mists is 10x more interesting then cataclysm.
also in what final raid did we not fight random nobodies most of the time? wrath is the only one that had a good bit of known characters but even then alot were random nobodies, in bt the majority were random nobodies.
i could see orgrimmar being interesting have gallywix there in some cool goblin tinker war armor have some dark shaman and some kor'kron maybe a demon or two.
hell even just gallywix in some tinker armor would be badass in itself and would let the goblins get rid of their prince