The placement of the enemies and such compared to the music seemed very off, it made it difficult to play, especially if the game lagged for even a split second it would throw the entire thing off.
Secondly, I really disliked the whole "kill" thing at the end of the battle part, it seemed a bit obnoxious, but some people might like it. To each their own.
I also didn't really enjoy the battles.. like at all.. I felt they were far too short and just sort of tedious and annoying more than anything. And on that note, the survival was a bunch of fun [other than the placement being an issue] but it actually seemed slow paced to me.. Which was annoying. That mixed with the enemy placement compared to when you need to hit them made the game overall more rage inducing than fun.
One last comment, the blinding sparkle/hit thing on survival from the big combos? I think that should be gotten rid of entirely. It was very jarring and definitely needs an epilepsy warning solely just for that.
I love music based games in general, rhythm or otherwise, but this was overall a drag for me other than the extremely nice visuals.
It's a great start though! Keep up the good work, and get that stuff fixed.