Hi TKSalt, sorry for being a bit late, but here's my mod for M4M :3
All here are just suggestions, feel free to ignore any of them if you don't like, the mapset is already nice for me.
[General]
No errors in metadata, timing and folder. Clean.
[Kantan]
00:42:758 (65) - Maybe remove this, I feel a pause would fit nicely here.
01:18:008 (126,127,128,129) - How about a d d d K pattern here? This way the big kat would sound nicer in my opinion.
01:19:508 (130) - Maybe remove this? The finisher before would feel even better if it was the last note to hit in this part.
01:42:758 - Add a note here? This part feels a bit empty as the beats here are quite strong.
01:50:258 (176,177) - Add a note between these two and make the resulting pattern d k d, like the previous one?
02:21:383 (48) - Maybe use a don here? Like I suggested in 01:18:008 (126,127,128,129).
[Futsuu]
I'd suggest you to change the dkd and kdk patterns in 1/2 to either ddk, kkd, ddd, or kkk, I think they may be a bit hard to handle in Futsuu. This would require adjusting the notes around these parts, but this depends of your style
01:12:758 (186) - Remove the finisher?
01:18:570 - Add a note here? This part is a bit intense, so a note would fit here.
01:42:758 - This would add a bit of difficulty, but a note is definitely missing here, hitting the 2 big kats after a 3/2 beats feels a bit weird in my opinion.
02:12:758 (55) - Remove the finisher?
02:21:570 - Add a note, like I suggested in 01:18:570.
[Muzukashii]
00:17:726 (67,68) - You could remove these notes and add a note in 00:18:195, to follow better the instrument playing there (viola-like), if you do, you could also remove 00:18:945 (73), to follow it better.
01:39:195 (382) - Maybe remove this to keep following the piano nicely.
01:42:195 - I feel a note is missing here, try adding one here, if you do, remove 01:42:664 (394) to not make the pattern too heavy.
01:57:383 (10) - Use a kat here? I this would be a bit more consistent with your patterns in the previous kiai and more intuitive in my opinion.
02:03:383 (37) - ^
01:55:883 (3) - Maybe here too.
02:01:883 (30) - ^
[Oni]
01:19:883 - How about making a kd dk rhythm here, instead the k k k you have? That way you'd follow better that instrument-whose-name-I-can't-remember.
01:21:945 - A don would fit nicely here, same reason as above.
01:22:883 - And same suggestion about the kd dk rhythm.
[Inner Oni]
00:15:945 (96,97,98,99,100) - Try ddkdk? :3
00:18:570 (119,120,121,122,123) - Try ddkdd? <:
01:42:851 (695) - How about removing this note and making 01:42:945 (696) a big kat, it'd fit better I think.
That'd be all from my part, good luck /o/