I think another great idea for thief would be adding a spec that revolves around counterattacks. So the majority of the weapons skills would be based around the idea that if you say block an attack you get access to a new skill for a short period of time or if you interrupt your foe you can knock them down or something like this. This is not something that is new to the game but to my knowledge there are no specs or classes that are entirely based around counterattacking and I think thief would be the ideal candidate. As of the weapon I'm still leaning toward greatsword. :)
