As I was playing I literally thought 'this is a really cool idea, but I wonder if it would be better if the player had a ____' and then hardmode answered my prayers.
Love the atmosphere both modes go for (and the music!) but enjoyed the faster pacing and extra features of hardmode. Also loved the extra feature of asteroids and debris interacting with each other. That was a really nice touch. One thing I noticed, the trajectory should maybe change to negatives when going one way off course and positives the other way to differentiate.