Following are my personal suggestions:
Normal:
02:59:140; I think this silder is a little unsuitable to the rhythm, it's better to replace it with 5 circles, OR if you prefer silder but not circles here, you could design it like this:
instead of the previous one
Hard:
00:44:140; Swap the position of circle 5 and 6
01:43:240; It better to coincide three circles like this:
because it's coincide with the whole layout
02:14:140; reset this circle like this:
02:16:540; Same to the above one
Insane:
01:13:540; The silder is longer than the rhythm, change it like this:
instead of the previous one
after that, you could redesign the shape of that silder
01:15:940; Same to the above one
03:15:340; replace the silder with one finish circle, OR you could add a new timing here, and set a lowest velocity for that silder to make the slider shorter
In total, It's a good map, well-done in layout and rhythm, good luck on mapping~ ^ ^