Boss battles were challenging and difficult to master (Nice!)
Progressing through the game required buying new weapons thus harnessing that mechanic (Great!)
Music and graphics were interesting.
The text could be better if a little bit sharper and clearer.
Maybe this devblog for setting up Godot for such low resolutions can help?
The size of the download was astonishing.
Maybe some assets could be made smaller.
Compressing music/images into a different format?