If you didn't notice, FF series go in this order starting with FF1 & FF2. It's even been agknowledged by Squaresoft themselves that they try to keep to this order.
Better Gameplay
Better Story
FF1 - New Gameplay, barely any story.
FF2 - Great story, convoluted gameplay design (easily exploitable even)
FF3 - New Gameplay (Job System), barely any story.
FF4 - Great story (though much was lost in translation), OK gameplay design.
FF5 - New Gameplay (Job System revamped), barely any real story.
FF6 - Great story, some consider the best so far, OK gameplay design
FF7 - New Gameplay (3D, new system), also invented new standard: eyecandy
FF8 - Better eyecandy, better story, bad gameplay
FF9 - Excellent gameplay with a lot of oldschool references, OK eyecandy
FF10 - Good story, better eyecandy, OK gameplay
FF10-2 - New gameplay (Job System reborn as Dress System), OK story, borrows heavily from FF10
FF11 - Online game, good backstory with the ability to choose your own destiny
This is one of the reasons they named it FF10-2 and not FF12. I actually think this is a great system. This allows the various departments (design, programming, and art) all very much needed slack on certain projects, and allows them to do two projects at once much more effeciently (usually one project is started before another is finished).
What I do find odd is that fanboys across the nation are quoting FF10-2 as the end of Squaresoft because it shares elements with a previous FF game, yet Capcom has been releasing Megaman titles up to 9, each with the EXACT same format and sometimes sharing a lot of sprites (especially Megaman himself)! I never heard ANY complaining from those fans...