Sorry Vulkin, I assume I didn't make things clear enough. The mod went in a different direction than my intention, so I thought I had better not post anything.
Anyways, since the futsuu is actually in need of a buff, I'll do my best to arrange that.
So, let's talk spread first. The Muzu is substantially harder than the Futsuu, to a point at which correlations between Kantan and Futsuu are visible, but not between Muzu and Futsuu. Ideally, you'd want there to be an even spread between the two. The main characteristics that make the Muzu hard are triplets/quintuplets snapped on 1/4 and longer patterns. We ave limited options for the Futsuu, but we can try to apply some of those traits to that diff as well.
In order to do so, let's first work on emphasis. When I look at the breaks spread throughout the Futsuu, I get the impression that they are just there, without a proper sense of balance or consistency. This makes the parts that do not have breaks look a bit off.
00:27:953 - Consider deleting this note as t provides a consistent break pattern with 00:25:194 - . Starting to emphasize that extra note at 00:30:711 - is perfectly fine since the music is becoming more intense as we move through this part of the song.
01:03:125 - this note should definitely be isolated. There should not be a note 1/1 later, since it takes away the emphasis of the previous note.
01:20:367 - You could technically get rid of this note as well, just to increase the emphasis on 01:19:677 - .
02:03:815 - This note also lacks emphasis due to 02:04:160 - being so close.
02:25:194 - I wish this was a don finisher to make a little bit of a difference in terms of emphasis. You used d k k three times out of four, so using this pattern at the end doesn't add anything, even though the music gets a lot more tragic towards the end there. a kat finisher also does the job.
You can keep all existing breaks, if they don't happen to be modded out by the following bits.
00:13:125 - Please add a don here, as you were following the bass synthesizer.
Please add dons at 00:17:780 - and 00:23:298 - to keep it consistent with the current don doubles.
00:32:780 - I wish there was a kat here, just to emphasize the synthesizer. It sort of feels like you can't decide on what to follow here, so parts of this section follow the vocals and parts follow the instrument, which doesn't appear as too consistent or clean. I'll just make you follow the synthesizer primarily for rhythm and the vocals for colour choice, if that is okay with you.
00:35:194 - Please add another k here to include the synthesizer.
00:36:056 - This doublet is not consistent, this is the only part at which it appears. I assume that you meant to follow the rising synthesizer sounds that appear in doubles, and that is fine, but you need to keep that consistent so that you don't make it look like you placed it there randomly. You have a couple of options for that, you can either add notes at 00:38:815 - and 00:41:573 - or you can increase the density generally by emphasizing this rising sound more often, for example at 00:36:573 - and 00:36:746 - by simply adding two ks. I'd do this for every part of the section once (i.e. 00:39:332 - , 00:42:091 -, excluding the last one; please keep the vocals in mind when placing colours).
00:56:056 - You can add a don here if you want.
01:00:884 - This rhythm right here is slightly free-style. However, it'll be fine if you just add a k at 01:00:711 - .
01:06:401 - A don would fit really nicely here.
This is just a suggestion, but have you considered starting your sliders on 01:54:160 - and 01:55:539 - , placing a note at 01:56:918 - ? You know, downbeats and stuff just like in standard.
02:02:436 - to 02:03:470 - generally kind of lacks emphasis, I'd use a different pattern altogether. Consider using, starting at 02:02:436 - : k d k k d k d d. This pattern stops at 02:03:642 - , and is snapped on 1/2s. Furthermore, if you get rid of 02:03:815 - , you can make 02:04:160 - a finisher. This makes sense due to the delayed high note climax.
02:13:125 - I'd add a don here to include the snare.
02:14:332 - a kat at this position not only increases the emphasis of 02:14:849 - , but also fits in nicely in terms of density due to the previous two doublets. If you change this, please add a d at 02:18:815 - as well.
And that'll be it! Good luck!