I've played Final Fantasy Tactics at least 15 times. Well, I was looking at Final Fantasy XII stuff and I noticed Balthier has the same last name as Mustadio! Plus, as far characters go they are some what alike. Mustadio's class in FFT was engineer and he used a gun, much like Balthier. Perhaps I'm just going all fan girly. Opinions?
I have not played XII yet so I am not familiar with the characters but I thought I heard somewhere that although they are in the same country I do not know if they are suppose to have any true reference to each other.
I believe that country (or is it a world), sorry that I do not have a better answer than that. For all we know his last name could be commen there like Smith is in the U.S.
But I think it is a great observation on your part and hopefully someone can give you a true answer