Radiant was sick, I agree that it's a slow starter but really it gets better with every episode, especially on season two. What sets it apart from other shows like it is the world, I can't really recall any anime taking place among floating islands except Shuumatsu Nani Shitemasu ka Isogashii desu ka Sukutte Moratte Ii desu ka and maybe some other flight/pilot related anime but I cant remember if there were floating islands involved, maybe last exile? Anyways, the world is interesting the animation is pretty slick and while the story might be a bit generic the execution is p good.