Easy and Hard are good, I only have a few suggestions for Normal.
Call me back after fixing/denying these.
00:05:440 - To emphasize the vocals a bit more, I'd prefer it if you have a slider here, with a repeating slider at 00:06:583 - with a whistle on end of the first slider and the middle repeat of the repeating slider.
00:24:298 (5) - This slightly touches the HP bar. Please look at that.