We apologise for the initial low quality review. Here is a review from a new judge:
Your game shows some solid principles and as a fan of rhythm games I enjoyed the challenge of it, however it has plenty of room for improvement.
GDD
Your GDD shows a good vision for the game. You clearly lay out how you want each part to be like. It'd be great to have some more details on your plans for artistic direction, maybe a sketch for how you want the main gameplay to be laid out, and some planning around your target playerbase would be good to see. I like the prioritised to do list.
Art and UI
I found the art throughout the game to be alright but not all elements were very cohesive with each other and sometimes lacked consistent proportions or amounts of detail. I think with some more iterations and polish it could look quite good.
I liked the floaty menu UI. The rest of the UI however could use some more work making it clear what's what and could do with following some UI design principles for layout and distinguishing what different things do/mean.
Music
The music was great. I especially liked the spacial audio. Maybe that could be correlated with where the enemies are coming from in the future.
Playability
The game was lacking quite a lot in playability. While it may be generally familiar to those who have played similar rhythm games before, there was no indication of at what point you were meant to swing at or whether you were early or late in your swing. A tutorial would have been very much appreciated.
Overall I believe this game could go far with some work. I hope you continue working on it!