You've got a solid foundation here, looking forward to seeing where this project goes! The fundamental gameplay loop is satisfying, and though I think there's some tweaking to do with the difficulty scaling as you get further into the run, overall things feel balanced and challenging without feeling too unfair.
That said, there is a significant difficulty spike at about 800m that seems to kill most of my runs. Random run-of-the-mill enemies seemingly go from dying easily and not hurting much to being nigh un-killable and obliterating me in 1-2 hits. I wouldn't complain if that gets smoothed out a little bit.
Out of curiosity, any plans for a "final boss" of sorts? Or a way to "complete" a run without dying?