Thanks for your mini review! One of the trickiest parts of designing IE was balancing the difficulty. I'm a fan of challenging gameplay so I wanted to make the bosses difficult, but I started to consider accessibility of the game: if it was too hard, then most players would probably drop the game after the first boss, which would be a shame since I'd want them to experience all the fights. Towards the end of development I increased the maximum ammo; lowered the damage of some enemy attacks; decreased the reload time; and gave the player more hearts after boss fights. This was just to ensure that more people would be able to beat the game. But for people that wanted more of a challenge, I also added 'Gauntlet Mode', where you fight all the bosses one-after-another, which would hopefully satisfy players who want more of a challenge. Try it out if you've got an itch for hardcore boss rushes!
I'll definitely take what you've written into mind if I tweak the game in the future, like perhaps adding higher difficulty levels. For now though, I'm glad you enjoyed Innards Exterminator!