Agree with Bob generally with the exception of XII which I think was only slightly melodramatic at certain points. But they are fantasy games - they need some melodrama. I think Vagrant Story probably got the balance very close to perfect in terms of story.

Oh, look at FFIV. People killing themselves left, right and centre (then actually not). People being brothers and related and so on - yeah, it was also fairly melodramatic. Can't remember V though.