I think storyline first and foremost. FF X was my first FF and I experienced much of the series backwards from there going to VIII to IX to VII then VI & I. I fell in love with the characters and their plights. I saw the FF series as a high tech and interactive novel. Without a strong story and cast it's easy to lose my interest like with FF XI, XIII and XIV.

XII was the only exception that disappointed me story and character wise but I still loved the game for the awesome adventure provided by the Mark Hunt system. Many fond memories fighting Marks there. Really excited to see if XIV's new NM system said to be able to level a whole class off nothing but Hunting NM's is anything like XII's Marks.