This is a blast to play! It's also a blast to watch someone else play, sort of like watching someone in an arcade playing DDR. You could lean into that vibe a bit with a score that builds with how many keys you've pressed correctly, if you wanted to.
I am not a fan of the font used for the keys, though. I got confused between H & M and D & O, and when the game starts to move fast, there's just not enough time to decipher which letter I'm seeing on the screen. Save the (admittedly fun) buddle font for headings, but have the keys remain in a more legible font, please!
Also, it's possible to "break" the game by just holding down every key on your keyboard through the whole game. It's hard to do, but it still is a way to kinda "cheat". Maybe have it so you have to lift the button press before starting the next one?
Finally, I just wanted to say that the music is excellent. Not only is it fun to listen to, it also matches the pace of the game well, and it makes it easier to keep the pace of the key presses!
Overall, this is a really fun game! Great job!