Heaven mode feels too difficult for what is supposed to be the more relaxing mode. I eventually got the hang of it, but I was getting tired of mashing to skip a cutscene that I was getting to for the 20th time. The especially frustrating parts were the boss attacks that took away what seemed like half of the health bar. While the small enemies posed little threat on Heaven, I still had to pay extremely close attention to the bosses and stage hazards; you can't make many mistakes through the whole run if you want to beat the final boss.
I enjoyed my time overall, but I was getting very frustrated at times for what is supposed to be easy mode.