Here are my opinions.
God Tier
Final Fantasy VI. The series blended serious moments with comedic moments and still didn't feel out of place. The battle system might have been broken with the whole evade bug, but i still enjoyed everything else about the game. Many characters, yet I felt that I liked most of them. None of them felt useless in battle. The soundtrack is amazing and the opening set the mood right from the beginning. And there's Kefka. He'd blend in perfectly on these boards.
Final Fantasy Tactics: The War of the Lions. Despite being totally unbalanced at some points and having level scaling random encounters, this is one of my favorite games of all time. I don't know how many times I have played both the PS1 and PSP versions. I guess I just love tinkering with the job systems and abilities. The story is also one of the better in the series. That might not be an amazing accomplishment, but it is true, nevertheless.
Final Fantasy IX. Let me start with the low point for me. The slow battle transitions. They kill me every time I play the game. I am also not a big fan of how Trance worked. It was annoying when your character got hit in a battle before a boss fight and the Trance had to be used up. Other than that, I guess the final boss was a bit of a letdown. Still, I loved the game. Again, just like Final Fantasy VI, comedy and tragedy both fit into the game. In general, I just loved the tone of the game.
Top Tier
Final Fantasy Tactics Advance 2. Liked this for the same reasons as FFT: TWotL minus the great story. The game was also perfect for making commuting less boring. Played a lot of it in bed, too.
Final Fantasy Tactics Advance. Liked this for the same reasons as FFT: TWotL minus the great story. The game was also perfect for making commuting less boring. Played a lot of it in bed, too.
Final Fantasy XII. Some people might not like the game, but I enjoyed it a lot. Have over 200 hours spent on different playthroughs. It's a damn shame we never got the International Zodiac Job System over here. A lot of people complain about the gambits and how they can set up one set of gambits and complete the whole game that way. That may work if you grind for hours, but not if you go through the game without grinding. It was the most challenging game in the series when you didn't power level your party. In many fights, I cam out as the victor with only a character near death as a survivor. I remember one fight where the only character I had left was poisoned and had about 100 HP. Sure, dungeons were longer than necessary and some characters shouldn't even have existed. Still, there was so much I liked about the game, that those things did not ruin the experience.
Final Fantasy X. It shouldn't be in the top tier when I think about it. It has so many things I think needed fixing, but I can't help myself. Every time I start this, I get addicted by the battle system. I have to fill the sphere grid and it has actual turn-based combat. being able to switch characters at will is also something I liked.
Final Fantasy: Type-0. Playing this on PPSSPP and it looks great. Managed to get it working with a DualShock 3 because I got cramps playing on the PSP. The combat is action based. I do prefer turn-based but the action based combat does work, I suppose. It's an evolution of the Crisis Core combat system. I haven't played much, so this game might actually change tier depending on how things go. I have stopped playing for now, in anticipation for the fan translation. What i did play so far, has been fun. You control three at a time, if one of them dies, you can call in a reserve character. You can also change your controlled party leader at any time. The Killsight system makes the game a bit repetitive and the strategy game missions aren't the best, but I can lie through that. Music is top notch and (Japanese) voice acting sounds good to me. Can't comment on the story as I don't know what is going on half the time.
Mid Tier
Final Fantasy VII. This one is somewhere in the middle of top tier and mid tier. There are many things I like about it, but there are many plot holes and the game hasn't aged well. At least not the character models while exploring. Translation was also a problem. The game has a great soundtrack, materia system is kind of fun to tinker with, mini games, atmosphere is great and it also has the best victory theme in the series.
Final Fantasy V. The story and characters are fairly forgettable. I play this for the job system. I remember beating the final boss without him getting a single hit on my party.
Crisis Core: Final Fantasy VII. had this been a console game, I would have put this in the low tier. The game has great music and the formula works for a portable device with missions being fairly short.
Final Fantasy XIV Beta. I played A Realm Reborn on both PS3 and PC. I don't play MMOs anymore (not that I actually invested much time in any of them), but had to try this out. It was fun playing with a friend and it actually felt like a Final Fantasy game. It was way better than all the FFXIII games we've gotten this generation.
Low Tier
Final Fantasy XIII. Biggest disappointment after FFXII. FFXII offered a big open world with great voice acting and mostly interesting characters. I was hyped for this, more than I should. We all know what the result was corridors and crap dialog and writing. The reason it doesn't go into the shit tier is because of the music and graphics in some places. And some of the hunts were fun.
Final Fantasy VIII. It had some good things about it, but it has one of the least enjoyable stories in the series. Also, it has more plot holes than any other game in the series.
Final Fantasy I. I have replayed this once or twice. It isn't terrible or great, it just feels basic.
Final Fantasy II. I haven't played this in over a decade, so i don't remember much. However, I do remember trying to force myself to finish it.
Lightning Returns: Final Fantasy XIII Demo. Yes, I only played the demo, but it was enough for me to decide against buying the full game. I'm not one that hangs himself up on graphics, but the game felt like it was all over the place both from a design point of view and a technical mess. battle system seemed decent and gave me Valkyrie Profile vibes.
Shit Tier
Final Fantasy IV. Grind, grind, grind. Crappy sotry and everyone dies just to come back at a later point.
Final Fantasy Mystic Quest. Wtf is this shit?
Final Fantasy XIII-2 Demo. Only played the demo, but I can't stand serah. Plus, they removed some of the abilities like Haste and some other stuff. Game was too streamlined and easy.