FFV is like my third favorite FF. I felt the story was great but the characters were a bit lacking. It wasn't anyones fault really. More of system limits, like FF4. I wish there was more dialogue between them. However, the greatness of the game lies in the job system. That is my first experience to the job system and to me it's the only bearable version.
However, Zeality, you thought ExDeath wasn't human? Well that was kinda the point. He was meant to be pure evil. Villain behavior has always been great in FF, if you ask me, save Ultimacia. They fit their bill. If you don't like him, it's prolly the character style you don't like.
But I should stay out of this, seeing as I have yet to kill Neo-ExDeath. (because it's impossible without grinding!!!!)