Thank you for your thoughtful exploration of the game!
I'm glad you enjoyed the hard mode in the mirror maze! I wanted a little challenge in the game, but not everyone likes a bunch of gameplay in visual novels so I made hard mode optional. The ERROR and dog park endings were fun to write since they're meant to make you feel like you're doing something you shouldn't that messes with world in the game -- making IT take notice and start speaking to you more directly.
Thank you for trying out the game, I'm glad you enjoyed it!