00:04:503 -> 00:06:234 - This part get really messy in the lower difficulties, i'd suggest removing it completely in futsuu and muzukashii because the sounds are very quiet, does not really follow well the kicks and has unpredictable rhythms overall which makes it not worth mapping it.
00:21:234 - Consider adjusting the nc finisher by placing a omitted redline here then add an other one here 00:21:618 -, same for 01:13:546 - 01:13:930 -