I can confirm spawning happened across the play area for me. In my first couple runs I made some noob mistakes but then had a fantastic run for a beginner, about 40ish dodges. I think you added a great jamming audio track that enhances the game play, I'd like to hear a few more jam tracks and some sense of level clearing. 

The squares seem to only spawn in the top left leaving the rest of the playable area as essentially a safespot. Maybe as the level goes on that changes but I got a bit bored before making it that far. Still really solid fundamentals for a bullet hell type game so I bet with some more time this could be something special