I have to share Bill's sentiments. This wasn't exactly a heavy-weight series to begin with, though of course not without any depth either, so keeping things in the right proportions this succeeded quite well in my opinion.

I it also visited my mind that Otonashi's situation reflected the shadow master's quite well after Kanade disappeared but I still doubt he could ever be him or even become like that. It hardly fits together with the fact he knows everything already. He can't really first help someone disappear and then keep eternally waiting for that soul's return. For he did indeed help her and willingly. It's not like a dude like him would have doomed somebody he loved. I reckon he disappeared himself right after catching his breath again. He could have disappeared a long time ago, after all, if he hadn't felt like helping the others.

A good series all in all even if it didn't quite reach such heights as some earlier Key works have. But at least we had the most cute Angel in this one!