Glad you like my game even when it's over difficult. Ya! It's hard to do game balancing. And a 3d bullet hell is really a game mechanic hard to design, maybe that's the reason there is not many reference on the market. I know Nier:Automata but haven't played it, maybe i should some time on it.
As i like the setting and the interesting at this uncommon mechanic. I will keep trying it with more sequel until it works. Your feedback is very helpful. Thanks a lot