Yeah, I agree about the difficulty level. XII fixed most of it, since I was actually satisfied with beating the Undying and fighting Cid was hard, but not frustrating - just made you think faster. It was a great improvement over X, where you could beat Yu Yevon blindfolded.
XII is my favorite FF as of yet but it also has one of the worst flaws - the leveling is very unbalanced. I found myself stopping to grind a lot and I found the fact that only the party members that took part in a battle received XP disappointing. This made half of your party relatively strong and the other one really weak.