-Mechanics can be separated into two categories: mechanics that are ignored and mechanics that will instantly kill/wipe if ignored.

-No sense of urgency or importance of resource management.

-No sense of urgency or importance of threat management (save for white mages in the first few patches of 2.x)

-Tide of battle is too decisive. Many encounters rely on a "go, go, stop" feeling where there is no gradual sense of gaining/losing an advantage leading to a win or loss. Wipes are frequently "triggered" via missing a specific mechanic that leads to an almost immediate failure of the encounter.

-No feeling of customization. 30 points into one stat standard. Secondary stats feel irrelevant.

-Overused positional mechanics.

-No flexibility of limit break system. Each encounter is very suited towards one specific type of limit break.

Just my two cents.