It keeps in suspense, but ideology of the ending is extremely naive.

I've just finished this series.
For me it's a bit like a mix of Death Note (the motive of a teenager gaining unnatural powers by accident and using it to fight evil and using his intelligence to play it all out perfectly, but then finding other one with the same purpose but an inverse method) and Hellsing (the motive of a war between one country trying to save itself from aggression of another great empire and a single hero helping the first country to survive due to his superior powers).
It's ability to keep your attention is surely one of it's biggest assets. Unfortunately the rest is not that great.
The weakest side of this anime are its holes in the plot, completely illogical twists of action and behaviour of some individuals and a completely misguided idea of peace at the end. The anime tries to convince us that by concentrating people's hate on a single target and then eliminating the target, this will lead to a world of hippie peace. But it's only within this anime and has nothing to do with reality. People do need some constant enemy, especially the ones who we call right-wingers and as fast as one of them disappears, they seek for another one to fill in the gap. Did the world's conflicts end with Hitler's death? With Bin Laden's death? With Ted Bundy's death? Everyone knows the right answer. So in the end the last part of this anime unfortunately makes absolutely no sense.