Just my opinion, I'm also disappointed in XII
I really liked the gameplay because I hated the annoying random battles. I just got tired of the loading times and it was especially painful in IX. However XII's battle system became extremely tedious and it probably had to do with the intensely long dungeon crawling. All those endless mazes aren't even that rewarding. I mean, all that for a little cutscene? And right after that, off we go to yet another 10-hour long destination. I thought it was hard to appreciate the plot because I always got off track on what the heck was going on.
It's been several months since I completed it and I believe it's the least memorable FF I've ever played. The characters seem to be forced to interact with one another from time to time. The only reason I even remember the main characters is because their names are listed right there in the main menu screen. Only Balthier and Fran (I LOVE her voice) are remotely interesting. Penelo just doesn't seem to have a purpose to be in the party.
The plot is okay, but nothing memorable or special. It's not my cup of tea. The characters don't seem to have much depth and bored me. By the time I got to the final dungeon, I was surprised. I know it was 60-70 hours since I started playing but whoa, I didn't realize the story was coming to an end. I thought the story was just unfolding. I understand that it's plot-driven which is different from the previous FFs but I don't think it was executed as well as planned. I don't mind not having a love story, though.
The music for the game is a complete letdown. Nothing memorable except the signature FF themes (such as the victory music).
XII's strong points are the battle system which I absolutely love, and of course the graphics. Other than that, I wouldn't bother playing this game ever again. High expectations might be the reason, but I did give it a fair shot and I still can't get into it.
I had to let it all out. I think FFXII is okay but not great. I enjoyed the game thoroughly and I never "forced" myself to finish it, but I admit I did enjoy the other Final Fantasies a lot more.