General:
-- Imo you should remove "Short Ver." and "Long Ver." from the difficulty names "Marathon" implies it's going to be long anyway and since you have two "Short Ver." I don't think its necessary.
-- You should make the volume level the same for all difficulties.
-- Kiai + white notes + light BG =.="
-- Add FuukoLover to tags on all difficulties.
Normal (Short Ver.)
-- Remove audio lead in.
00:57:963 (2,3,4) - Respace this so it's easy to read, it wasn't very intuitive. (I guess you could remove the very small returning sliders completely...)
01:50:463 (5) - Remove new combo?
02:05:463 (1) - Remove custom clap?
02:06:588 (3) - ^
02:10:713 (1) - Use custom clap (reduce volume a little).
Hard (Short Ver.)
-- Remove audio lead in.
01:00:213 (1,2) - These two x2 sliders are quite unexpected, are they really necessary?
01:18:775 (5) - Sounds better with just a single beat at 01:18:963 imo.
02:10:713 (4) - New combo? (Like Normal...)
Sayonara Fuuko:
-- Remove audio lead in.
-- You should probably add "Short Ver." here to I guess =/
01:04:713 (2,3,4,5) - Tricky to read 5 because it's so close. Might work well if all was stacked?
01:32:463 (2,3) - Spacing? (Feels too close)
01:33:025 (3,4) - ^
01:33:588 (4,5) - ^
01:35:463 (1,2,3,4,5,6,7) - Spacing? The slider velocity sped up but the spacing stayed as if it was x0.5 it didn't play very intuitively imo.
01:37:713 (4) - New combo?
01:39:025 (7) - Right one square?
Marathon:
-- With a score of 25million I guess this is for approval?
-- Remove audio lead in.
02:05:463 (1) - Remove custom clap? (Or lower the volume I guess)
02:05:650 (2) - ^
02:06:025 (4) - ^
02:06:588 (6) - ^
02:07:713 (7) - ^ (Imo soft whistle would be more suited in these places)
02:10:713 (1,2,3,4,5,6,7,8) - Custom clap might work well here.
04:06:213 (3,1) - Spacing? Jump felt a bit weird.
04:18:775 (5) - New combo.
04:20:463 (5) - ^
04:21:025 (1) - Remove new combo if you do ^
04:21:963 (5) - New combo?
04:23:275 (1) - Remove new combo.
04:39:400 (3) - Doesn't fit, two beats would be better imo.
05:36:213 (1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16) - The overlap with this stack doesn't look very good here, you might want to move it a bit further away from 05:36:025 (4) -
Nice mapset overall.
~ Star.