I found the whole second half of the series to be dull and annoying.
The first half felt like watching Sailor Moon. You had one duty per episode and once it was completed, that was the end of the episode, all for it never to amount to anything until the big boss just magically decides to appear.
The second half felt like overkill of various characters going bye-bye and them building up for Shu to die only to have Inori go in place of him. If they thought that would seem romantic, I didn't feel it quite so well... They rarely showed emotions towards each other. Ironically, Shu worrying over Inori and the kiss were the only "romantic" pieces to it. Compare that to my favorite pairing, I dare you; but it was worse than watching a shounen-ai.
I personally think the whole Mana bit was overrated and horrible. Bringing her back in the second half was a bad idea. The whole series was too religious for a lot of people to understand already, then they insert the crap about an Eve.
I really felt they built Shu up to be crippled and blind. They literally abused his character throughout the whole series anyway, giving him the most wish-washy roles imaginable... I saw it coming, in a way. Him living was something I had not seen coming.
BTW, what the hell is this? They're making a sequel? I think the apocalypse is coming...