On difficulty It really depends.. on Younis Story I could work better on calibrating difficulty and make something intentional about it, but for Seok part not at all, It was for most a burnout side effect cause. I was working with clickteam fusion and many things i implemented wasn't working at all for reasons I can't explain, the engine in itself's a mess, a black box, It happens quiet a lot that a function doesn't work and if you delete it and reproduce It exactly the same way or works but it's impossible to predict why. The shoot them up thing was entirely remade from scratch twice and at some point i was late on my work cause i had to complete the Younis part, so I focused on it and did it, but the level design aspect of Seok was just a nightmare, nothing was working properly and it was rather way to easy or way too hard, so i prefered to make it "hard", even if yeah, it's not like some i wanna be the guy thing but... just a real mess and at some point i was just about to give up.
Otherwise, regardless of the engine, that was probably way to ambitious and i could make something cleaner with something with a lower scale.