I think that you are either a FF8 person or a FF9 person and hate the other game, with everyone other than trolls liking FF6 and FF7. FF10 is the best all round game, or will be until FF7 ups it's graphical game.
FF12 is half finished. FF13 is shit.
Possibly. I hated FF8 the first time I played it. I went back about 5 years ago and played through it again and it was a bit better but still not great. I really didn't like the story or the characters (Quistis is kinda hot but that's about it). I also feel that they perfected the Materia system in FF VII and the Junction system was annoyingly convoluted just for the sake of being different. Then there was the magic system (draw mechanic) and enemies that leveled with you. Just a lot about the game I didn't like. Again, I think they realized that VII was lightning in a bottle so they made a ton of design changes so people wouldn't say "Oh, VII did this better."
I liked 9. It was a solid entry into the series but extremely underrated. The Necron piece tacked on the end never really bothered me. It was more of a "huh? OK, whatever let's just kill it" feeling for me and I didn't allow it to ruin the game. The characters were all very well done with a major theme behind each one. It was also the last "traditional" fantasy in a series called Final FANTASY.
I've only played 12 once. Never got around to a replay. I like the description that it was a single player MMO because that's how I remember it. I also remember running my guys up to an enemy and then going AFK to make a sandwich and coming back to collect loot... Terrible design in my opinion but if it was remade I wouldn't mind giving it another go to see how I feel about it today.
13 had a great battle system but was really flawed. I also think it was asking WAY too much to have Lightning carry XIII-3. She's simply not likable enough and with her terrible personality she can't carry a game on her own.
Loved 10 though. Probably my favorite in the series. This one seems to be one of the more polarizing ones. People either really like it or really hate it. Some of the voice acting was terrible (the laugh scene...) but the story and characters were fantastic. The battle system was solid. I don't mind a traditional Attack, Item, Magic, Run system. Not every game needs to be twitch gaming or button mashing to victory.