00:10:140 (1) - D - Because there's bass emphasis
01:32:245 (4) - d - It seems to fit the song and the rhythm.
02:01:298 (9) - Same as the first line

00:10:140 (1) - Same as Kantan
00:49:929 (22) - k - Because it fits the vocal pitch and it will give a bit of variety for the pattern.
01:40:456 - Why is here no note; It looks empty and inappropriate
02:01:298 (18) - Same as the first line

00:10:140 (1) - Same as Kantan
00:38:403 (4,5) - d triplets here please, the music totally calls for it
02:01:298 (27) - Same as the first line
02:20:245 (1,2,3,4,5,1,2,1,1,1) - This is kinda problematic, these are monostreams so 'maybe' it is okay, but I'm pretty sure it will be poked at by future modders.. well
02:25:929 (1,2,1,2,1) - Listening to the samplings, I think kkk d is good for this part

00:10:140 (1) - Finisher here, because here's bass emphasis
00:27:587 (1) - Move to 00:27:666 - . Is it a convert or something ._.
00:32:640 (2,3,4) - dd d seems better to follow the rhythm.
01:53:482 (1) - Move to 01:53:561 -
02:01:298 (1) - Same as the first line.
I see some varieties of patterns.. Nice diff

00:35:245 - Add a note here pls, there's sound, and this is not lower diffs and is Inner Oni, so why not
00:37:456 (3,1) - ddk pls. dk doesn't seem to fit the rhythm and song itself, and also looks/sound odd
01:50:561 (3,4,5,1) - dkdk fits the trumpet sound.
02:16:140 ~ 02:16:456 - No note? o_o

AR > 3
CS > 4

patterns are fine~

AR > 4
CS > 4

yikes, this is a big jump in difficulty from Kantan. I'm gonna suggest some places where notes can be deleted to give breaks.

00:11:719 (6,7,8,9) - two pairs in a row? Well, it's alright I guess, but this part is a lot less frantic compared to later in the song. I suggest either removing 00:12:192 (8) or 00:12:666 (10) in order to give a break
00:16:771 (22,23,24,25) - ^
00:20:561 (3,4,5,6) - again, I'd suggest removing 00:21:035 (5)
00:21:508 (7,8,9,10) - four notes in a row in Futsuu? Yeah, I know it's 1/2, but I'd suggest not going over 3 notes in a row. Maybe delete 00:21:982 (10)?
00:23:087 (13,14,15,16) - again, I'd highly suggest removing 00:23:561 (15)
00:24:035 (17,18,19,20) - for this, I'd suggest moving 00:24:508 (20) to 00:24:666 and changing it to k, there's a very noticeable cymbal crash here
00:26:877 (28,29,30,31,32) - suggest removing 00:27:350 (31)
00:31:613 (6,7,8,9) - suggest removing 00:31:771 (7)
00:34:140 (16,17,18,19) - similar to ^
00:35:403 (21,22,23,24,25) - suggest removing 00:35:877 (24)
00:36:666 (27,28,29,30,31) - similar to ^
00:41:719 (6,7,8,9) - there's a constant bass beat through this section, I'd suggest moving 00:42:192 (9) to 00:42:350, that way you can shorten it to 3 notes and have a beat emphasizing the bass as well
00:44:245 (16,17,18,19) - same thing here ^
00:45:824 (2,3,4,5,6) - suggest removing 00:46:298 (5)
00:47:087 (8,9,10,11,12) - 00:47:561 (11)
00:48:350 (14,15,16,17,18) - for this, I suggest removing 00:48:666 (16)
00:41:719 (6,7,8,9) - same thing, move 00:42:192 (9) to 00:42:350
00:44:245 (16,17,18,19) - same thing, move 00:44:719 (19) to 00:44:877
00:45:824 (2,3,4,5,6) - suggest removing 00:46:298 (5)
00:47:087 (8,9,10,11,12) - suggest removing 00:47:561 (11)
00:48:350 (14,15,16,17,18) - suggest removing 00:48:666 (16)
00:56:877 (6,7,8,9) - suggest removing 00:57:350 (9)
00:59:403 (17,18,19,20) - suggest removing 00:59:877 (20)
01:01:929 (6,7,8,9) - suggest removing 01:02:403 (9)
01:06:982 (6,7,8,9) - suggest removing 01:07:456 (9)
01:09:508 (17,18,19,20) - suggest removing 01:09:982 (20)
01:15:824 (4,5,6,7,8) - suggest removing 01:16:298 (7)
01:17:087 (10,11,12,13,14) - suggest removing 01:17:561 (13)
01:18:350 (16,17,18,19,20) - suggest removing 01:18:508 (17)
01:19:613 (22,23,24,25,26) - suggest removing 01:20:087 (25)
01:22:140 (6,7,8,9) - same thing, move 01:22:613 (9) to 01:22:771
01:24:666 (16,17,18,19) - same thing, move 01:25:140 (19) to 01:25:298
01:26:245 (2,3,4,5,6) - suggest removing 01:26:719 (5)
01:27:508 (8,9,10,11,12) - suggest removing 01:27:982 (11)
01:28:771 (14,15,16,17,18) - suggest removing 01:29:087 (16)
01:32:245 (1,2,3,4,5) - suggest removing 01:32:719 (4)
01:37:298 (6,7,8,9) - suggest removing 01:37:771 (9)
01:39:824 (17,18,19,20,21) - is the lack of d at 01:40:613 intentional? if not, move 01:40:298 (20) here
01:42:350 (6,7,8,9) - suggest removing 01:42:824 (9)
01:47:403 (6,7,8,9) - suggest removing 01:47:877 (9)
01:49:929 (17,18,19,20) - suggest removing 01:50:403 (20)
01:52:456 (28,29,30,31) - suggest removing 01:52:929 (31)
01:54:982 (39,1,2,3) - suggest removing 01:55:140 (1)
02:08:877 (2,3,4,5,6) - suggest removing 02:09:350 (5)
02:11:403 (2,3,4,5,6) - suggest removing 02:11:877 (5)
02:12:666 (8,9,10,11) - try moving 02:13:140 (11) to 02:13:298, if it doesn't work for you try removing itr
02:15:192 (7,8,9,10,11) - suggest removing 02:15:666 (10)
02:22:771 (1,2,1,2) - suggest removing 02:23:245 (2)
02:27:824 (1,2,1,2) - suggest removing 02:27:982 (2)

I know you might not like it, but please consider at least some of the above changes, since I don't think Kantan can be any harder, so the problem of the difficulty jump has to be dealt with in Futsuu. I'll admit that it might make the difficulty jump from Futsuu to Muzu a bit wider as well, so find a medium.

00:17:719 (1,2,3,4,1,2,3,4,1) - ...I think first-time Muzu players will be unpleasantly surprised with this, it's a little too much out of nowhere. Consider removing 00:17:877 (2) and 00:18:508 (2) so players have a bit of time to recover after hitting the finish.
00:30:508 (2) - I'd recommend either removing this note to let players recover after the finish, or removing the finish itself, depending on the music, but it's up to you (applies to all other streams starting with a finish note)
00:35:403 (1) - the cymbal crash here sounds more subdued compared to the one a moment later, so maybe consider removing the finish to make it play better?
00:35:403 (1,2,3,4,5,6,7,8,9,10,11,12,13,14,15) - this is a long stream without breaks, consider deleting 00:36:508 (8) since the result flows better with the vocals.
00:45:508 (1,2,3,4,5,6,7,8,9,10,11,12,13,14,15) - this too. ^
01:15:824 (8,9,10,11,12,13,14,15,16,17,18,19) - ^
01:18:350 (22,23,24,25,26,27,28,29,30,31,32,33,34) - ^

Oh, I get it now, Futsuu is that hard because of Muzu's difficulty. I'll be honest, this is pushing easy Oni difficulty, and I know you probably don't want to reduce Muzu difficulty much, so find some way to work with what you have~

00:19:771 (1) - add finish to this note as well? there's no bass drop or anything calling for a finish at 00:19:929 (2) but you added a finish anyway, so if you want to keep the finish here, I'd suggest adding it to this as well.
another massive jump from Muzu, tbh this feels Inner Oni-ish.

00:39:824 (1,2,1) - yikes, this SV. I'd really really suggest avoiding overlapping of notes at all costs, so if you reduce the SV to 1.25 it'll be fixed.
00:54:982 (1,2) - this one too, set it to 1.25
01:05:561 (1) - remove the finish here, so that the finish on the next note properly emphasizes the cymbal crash
01:13:140 (1) - ^
01:35:403 (1,1,1) - SV to 1.25
01:53:561 (1) - remove the finish, ^
02:01:456 - dropping all the way to 0.75 instantly is causing overlap, I'd suggest adding more green points to the preceding notes to gradually decrease the SV, or increasing the 0.75 SV to 0.9 (which will also include changing 02:08:876 to 0.9, I guess).
02:08:087 - I can't think of any way to not have overlap and still keep the speed up, so I'm going to suggest removing this SV change.
02:10:692 - SV to 1.25