I'm pretty late to this thread but I figured I'd put my two cents in.

My favorite FF is 8. I know a lot of people don't like it as much because they say Squall is a whiny emo, but I overlook it because I love it's character development. Well, the junctioning system. Most people hate it. I love it. I am not a fan of how they usually "assign" each character a Role.. I like to be able to do whatever with whoever. So yeah. I do like the story for 8 though. I highly recommend it.

I like 6 and 9 next. Even though they went back to roles in 9, it's still great. Music is STUNNING. Still my favorite FF sonndtrack.

Next tier is 10 and 7. Before I go on, lets clarify. Putting 7 here is not an insult to it - they are ALL high up there. I do love 7. It's a classic. I just don't think it's the greatest game ever, or whatever. The combat is nice and the story is cute. The world is my favorite part.. They did a great job of developing it and having lots of variety. The music is also AMAZING. 10 is .. I can never put my finger on why I enjoy it. The characters are mostly annoying, really. I do like the combat although I prefer ATB to complete turn based. Music is pretty good though and the visuals are nice.

On to 13... A lot of people hate it. And rightfully so. But I enjoyed it. I was only able to do so by NOT looking at it like an FF.. Because its really not. And people are right when they say the game is VERY linear until the end, and the characters suck. Even the music sucks. But the combat system is my favorite of any FF ever - and that's saying a lot. Seriously. I love it. It's so perfect. The paradigms, the classes, everything. Just perfect. I honestly could not think of a better system. The character development could be better, definitely. But the actual combat? Perfect. The rest? Not so much.

I guess X-2 fits here. I didn't really like it but it was nice continue the story from 19.

This one is where I rift from A LOT of people: 12. Seriously, this game SUCKS. I can't believe it even made it to shelves. Awful. Worst FF ever easily. I've tried to play through it so many times and always have to quit because its so terrible. I hate the characters and the combat SUCKS. I can't believe people like it.

I haven't ever played an FF before 6 so I don't really have an opinion on those. I know they're out for smart phones now but I just haven't had time.

Damn, this post was longish. I didn't mean to ramble so much.