A return to form
First things first. Yes the first half of the game is linear, why that surprises anyone given that every other final fantasy (bar 12) is exactly the same I don't know. Whether that makes this a good or bad game depends on your viewpoint. For me I like the controlled pace that it gives the narrative and find it helps me empathise greatly with the characters. Whilst 12 left you to wander for hours on end monster chasing with no narrative or character exposition this goes for the other side and it's something I much prefer. The story I think is superb and highly engaging, and the slow development and metamorphosis of the characters gives credence to the world they inhabit. Unlike the cardboard cut outs of the final fantasy prior our six main characters have depth, emotion and stories to tell, they have reasons that underpin the actions they undertake. Whilst the game dramatically opens up at the half way point (and maybe loses a bit of focus here, depending on what you like) you are by then fully engaged in the world, characters and story.
In terms of the world itself Cocoon and Pulse are highly evocative and powerful. Each area feels like it has a history and story to tell (not least the stunningly haunting Oerba) and this helps build a real and concrete sense of place. The only downside is the lack of 'towns' which feels a bit like throwing out the baby with the bathwater.
The fighting system is simply stunning, although at high pace can be hard to control, and lends the game a sense of spectacle usually reserved for the worlds and cut scenes. That said the game is hard, although mitigated by the ability to restart any fight after defeat rather than being sent back to the latest save point. Any miscalculation (even at maxed out levels) is ruthlessly punished and preparation is vital before many of the major encounters in the game.
Overall this a triumphant return to form for the series although I full accept that it will antagonise those outside of the usual fans of the series. The question really though is whether that is a bad thing. Entry 12 was revolutionary and well received critically but distanced the usual groups that enjoy the game. This is clearly (and it has been put on record by Square Enix) a game made for those already converted. A homage for the fans if you will, and for that I earnestly thank the developers.