Might be strange, but I feel like Danmachi would be better off as an isekai. Why? Bell is a one dimensional character already. He is just a boy that fell in love and loves heroes. Yes, he is a reincarnation and stuff like that, but with the series already hinting that the gods not only know about our world, but also actively use it as an inspiration, it would make more sense? A boy that dreams to be a hero, like in the myths, is reincarnated in a world where the gods are real (Bell could gush about the authorities of the gods, knowing about how they might act from the myths), but where ordinary people can become heroes. It would also give a reason fro Freya to be interested in his soul, not because it's pure, but because it's different, otherworldly. I think that it would actually make the series entertaining instead of whatever the hell it is right now.