Cleared the Byakuya route on Monday and am currently past two-thirds through the Anya route. My people from the end of the Byakuya route:
To be honest the game isn't that good. It's not BAD, but Kakusei was just better in pretty much every way. Of the new features the one I like most is the social aspects (the build your own castle thing) but a LOT of the problems with other stuff stem from the inclusion of it. The writing seems a bit stunted, the characters shallow due to the whole multiple route thing limiting the amount of time they get in one route. The customisation is bit limited compared to Kakusei yet skills are easily gotten through the social stuff, and either way a lot of the motivation to raise characters (for me, at least) is sapped away by the fact that you have to start over from scratch in the other routes.
The gameplay in the Byakuya route is terrible too, being way too easy for most of the game (it's not even Kakusei easy, it's clear stages on FUCKING AUTOBATTLE easy). The Anya route on the other hand (so far) does a very good job of limiting your resources and then tempting you with optional objectives that reward you with much-needed resources, and cool stage gimmicks, but quite a few of the stages are too tedious, and there are one or two that are plain bullshit unfair at times.