I agree with most all of what has been said. The game really only starred three characters (Balthier, Ashe, and Basch) but they were three pretty strong characters and I liked them all. The pacing was horrible. More than once did I venture on a sidequest, lose interest, and then forget what I was supposed to do to get the plot moving. Literally a year went by and I forgot all about the game. Finally I decided to plow right through it but a lot of magic was lost due to that large gap.
Dungeon crawling is fine when it's worthwhile. Hiking over large areas for one mark is not worthwhile. Mark sidequests just suck ass in general I've decided. It's such a weak way of giving the game a sidequest. Also throw some treasures along the way. FFXII's treasure system sucked and it made the exploring worse. This is not an MMO. I think SE tried to hard to make this game a single player FFXI.
A middle ground between FXII and FFXIII would be a great game. One thing FFXIII had was focus. Focus on character interaction and on getting to the end. FFXII could have used some of that focus. FFXIII could have used some of XII's NPC development and freedom.