As per Armin's mod4mod request:
[Easy]
At first glance, all I see are two tiny slivers of breaks. >> I guess they're long enough, though.
Wow, that first part is really boring. Try to spruce it up a bit, please~
00:30:805 (1) - This combo runs pretty long. Split it up.
00:36:036 (6,7,8,9,1) - Kinda iffy on an easy, but kinda okay. I dunno, heh.
00:47:113 (1) - The combo changes here feel kind of excessive. Maybe remove every other one?
00:57:574 (1,1) - Okay, this... yeah. Try mapping something else. The 1 after the slider may be hard to notice coming, and it may not be that intuitive as to when that slider is going to stop.
01:22:497 (1) - Super-long combo here.
01:26:497 (4,5,6,7,8,9) - This bit here almost feels like something that would go in a Normal.
01:38:805 (1) - Really long combo again.
01:44:959 (1,1) - Okay, these really don't fit the song at all.
01:59:728 (1,1) - ^
02:04:036 (1,2,3,1,2) - Spacing? Maybe find a better shape to form like a pentagon?
02:10:190 (1,1) - Those spinners again. >>
Yeah, just keep an eye out for really long combos.
[Normal]
Kind of a dull beginning again with the long repeating sliders.
00:08:036 (2,3,4) - Lower these one grid.
Keep an eye out for really long combos in this difficulty too.
00:28:959 (10,1) - Waaay too close.
I'll just say that I don't like the double spinners at all.
01:28:651 (5,1) - Rather close again.
01:44:651 (1,2,3,4,5,6) - This might be pushing it for a Normal difficulty. :/
01:57:574 (1) - Accelerated spacing in a Normal? :/
02:04:036 (1,2,3,1,2) - Kinda boring.
[Hard]
00:42:190 (6,7) - Maybe reform slider so there's less overlap?
00:49:267 (1,2,3,4) - Whenever this comes up, I lose a bit of health for getting all 300's. Make a new combo at 3 or something, please.
01:59:420 (1,2,1,1,1,1) - Really?
[Mukku's Monogata Hard]
00:58:489 (1,2,3) - Even up the spacing amongst these.
01:02:182 (1,2) - Was kinda weird to hear this rhythm suddenly.
01:57:566 (1,2,3,4,5,6) - Wow, uh, that accelerated spacing went a bit far, don't you think? Maybe lessen it a bit?
The main diffs could use some work, but they're not bad considering the type of song you're working with. And there you go.