X. Other than some very minor oddities(Blitzball, for example), I find Spira to be the most coherent Final Fantasy world ever, especially aesthetically. XII made the mistake of setting itself in Ivalice, the world used before for Final Fantasy Tactics. This is a problem because other than being told of the connection, there aren't any similarities: for example, FFT never mentioned the possibility that there were other sentient races living alongside humans, much less showed five (and counting!) of them. FFT being in serious contention for my favorite game of all time, I find this disconnect unnerving.
The combat system of XII irks me for several reasons, most of which are only relevant to boss fights when there is real danger of characters going down. One is the camera: it likes to get stuck so that I can only see a tiny portion of the field. If I want to see what the boss is doing, I can't see anything else. If the character I'm looking at is up against a wall, the camera may zoom in on them so much I can't see anything. While I like having position sort of matter, I don't like having to stop and try to figure out who is where.
Number two is retargeting, above and beyond the call of gambits. I had a boss fight recently with a flying boss where Balthier's #1
gambit was to attack fliers. But after the first shot, he retargeted the worthless minions on the ground! I ended up having to micro him to keep him shooting at the right thing. I've had the same problem elsewhere, where a character will ignore the wounded monster next to them to target one 10' away for no obvious reason.
Number three is the Queue. Maybe this is just my perception, but it seems to sequence actions, even the same action, together more slowly than Gambits do. And that pisses me off when shit goes haywire and I need to deal with unexpected problems.