I'm going to mix in some general stuff and errors, comment on the stuff you fix/don't fix, and ask if you don't understand something. If I'm online, you can PM me too for irc mod/clarifications. I'm thinking in 2-3 good general mods this will be an excellent map.
[general]
using symmetrical mapping looks a whole lot better. I'm not very good at this, but I like to throw in stuff every so often. Symmetrical sliders, however, to me make a big difference in how it looks. So if you could, read the
symmetrical slider guide and make things like
this look better. Don't forget you can use ctrl+shift+R to rotate sliders as well.
[hitsounds]
Unless you're confident about your hitsounds, I usually match hitsounds to what's in the song. There's a lot of cymbal crashes (finishes) in the song. If you want to copy the hitsounds I used:
download AIBat and export the hitsounds (under file->Export hitsounds), then copy/paste the bookmarks into osu. Then just put in the hitsound wherever there's a bookmark and a note.
I highly recommend doing this for finishes, but it doesn't matter much for whistles/claps.
A lot of the things that I don't think fit are because they slide over/onto an important beat. You can read a little more
here on why this is a bad thing.
[sekai]
00:24:470 (1,2,3) - these would look good if they were symmetrical
00:39:470 (1) - I think there should be a little more break in here, which is why I didn't even put a spinner over it in my diffs. You also only did this here, not later in the song.
01:20:030 - way too quiet.
01:36:155 (5) - doesn't fit
01:48:640 (1,1) - doesn't fit. Put one note on 01:48:620 -
01:51:245 (2) - doesn't fit. (slides over beat 1, which is the long white tick)
01:53:870 (5) - ^
02:00:245 (4) - ^
02:01:745 (5) - this is fine and fits the song.
02:06:620 (3) - shorten it 1/1
02:11:495 (8) - doesn't fit (slides over beat 1)
02:14:870 - I think you should but either a note or slider start here.
02:27:620 - too soft
02:33:245 (6) - doesn't fit, slides over beat 1
02:36:245 (2) - ^ but slides onto beat 1
02:37:745 (4) - ^
02:39:620 (4) - new combo
02:47:495 (4) - split into repeating slider and circle, put new combo on circle
02:56:178 (1,2) - as before
02:58:455 (4) - doesn't fit, slides over beat 1
03:04:830 (1,2,3) - slider ends messed up, and they are upbeat sliders. Make sure you put a circle/slider start at 03:05:205 on the downbeat
03:07:267 (5) - slider end messed up
03:08:205 (1) - move 1/2 earlier
03:09:330 (2) - doesn't fit, slides over beat 1
03:19:830 (1) - ^
03:22:455 (4) - ^
03:28:830 (1) - ^ split into circle, repeating slider
03:30:330 (2) - this is actually okay.
03:33:330 (3) - this one is fine too
03:35:205 - don't map anything past here unless it's one last spinner. I didn't do the right BPM and it slows down near the end, so it's almost impossible to map well.