I do not know about the difficulty (I was trying to start with Normal, but it was too easy, I quickly became not interested) Hard is pretty well balanced, well, you know ... I've seen quite a lot of those who played on Normal - the game goes through even if you are too lazy to think about your actions, even without a special understanding of what your characters want. On Hard there are crazy moments (like ignoring 0% hit chances) but in any case. The only thing I wanted to change in Kou - the number of points for opponents, if they were raised to the level of the remaining parts, it would be wonderful. I feel a strong lack of points for almost the entire game.
Аnd I like to replayed Kou, this is part of the story and there's a funny story.
Regarding the conservation, I think you tried to transfer NG +. This can not be done.