I'm always torn, when thinking about Kurono.
I still hope he'll be back soon. Just because I think that the story needs him. Katou is fine and all (he already has that good character that Kurono had to develop), but not as good a main character. I'm not interested in his struggel to live so that he can return to his little brother at all. That's not what I want to see in the time between missions, since I just find that boring.
In a way the Osaka arc represents how the story is without Kurono (at least to me). It was way too long and felt like a drag. Almost to the point where it wasn't fun to read anymore. Sure there were a few highlights like the number of times the osakans cleared the game, Oka and his death, and the HS swordfight but that wasn't enough for it to last almost 2 years. This arc didn't have the same appeal and drive that the story had up till this point.
And to me part of the reason is that Kurono is not there anymore.
But even though I want him to be revived as fast as possible (it has been two years after all), I know that he won't be back after this mission. Just because almost no time has elapsed since his death. It wouldn't make sense for him to be revived right now unless he would just live a normal life afterwards and won't play any part in the story anymore.
But one thing is for sure. If Katou will vow to revive Anzu before he does Kurono, I will be pissed.
Hope he realizes that he has to shape up and lose some of his good boy behaviour in order to get the job done, and then scores major points the next mission (to revive Kurono).
Which means, for the time being Katou will remain the new lead. But in the future I see him reviving Kurono and both of them doing the job together.
"For Feanor was made the mightiest in all parts of body and mind, in valour, in endurance, in beauty, in understanding, in skill, in strength and subtlety alike, of all the Children of Illuvatar, and a bright flame was in him"