general: something you can do to keep visuals as similar as possible is to make use of the copy-paste and other keyboard functions to keep your map's design consistent
take this part from your easy - 01:11:841 (2,3) - the two sliders have slightly different placement of the middle "curve point" and that makes them look slightly different
if you copy the first slider, paste it, flip it vertically with ctrl+j, and then put it into place, it will look exactly the same but mirrored. this helps a lot on lower difficulties where visual design is more obvious and more important (imo)
it would probably be really helpful to look at all of the various options in the top menu bar, particularly the ones in the edit tab:
if you've heard this before and just don't want to, thats also cool, that's just my opinion on mapping.
easy: overall pretty solid but there are some minor inconsistencies and other things
00:08:841 (1) - technically spinners are supposed to be 4 beats long in easy difficulties unless justified to be shorter. this isn't a big deal because it looks justified, but if you're going for rank you may need to point out that the song is a bit slower than most songs and it's most appropriate to end it where you did
00:12:270 (1,2,3,4,5) - i like that you repeat this set of 5 objects, but there is a longer guitar sound that starts on the beginning of every measure in this section
it makes more sense to have a clickable object - either the start of a slider or a circle - on each big white tick in this section.
you do the same thing twice more in that section - 00:16:984 (3) and 00:20:412 (3)
normal:00:10:341 (1) - really not sure about this spinner. most of it goes over complete silence, and it ends half of a beat before an important sound. at the very least it should end on the white tick (like it does in your other diffs), but probably just be deleted and replaced with a couple of circles
00:48:270 (1) - this doesn't really follow anything too well, and it feels like you were going for this kind of rhythm, which follows the piano:
hard: 00:01:127 (2) - here and some other places it feels like it would be more apropriate to just have circle or two circles rather than a slider - that particular word sounds like it's cut short and a circle represents that better
this sort of goes more into my own opinions on mapping and how vocal stress influences object choice
00:27:270 (5), 00:30:698 (5), 00:34:127 (5), things like that, consider splitting into 2 circles (or maybe you prefer what you already did)
00:33:270 (2,3) you could make into a single slider
basically focus a tiny bit more on trying to map the major voice sounds with clickable objects (and sometimes slider ends or reverses but mainly circles and slider heads) - you do a lot of this but it's not quite as consistent as it could be. those are the main ones i noticed, but try looking through and seeing if there are any others that could fit that pattern
00:02:841 (2,3) - these feel like they were shifted back a half step by accident. i know there's a piano sound on the head of 2, but the vocal falls on the red tick before the head of 2 as well as the tail of 2, and there aren't any sounds associated with 3. also the spacing looks like it was supposed to be the way i described
00:05:198 (3,4,1) - a bunch of other triples during more intense sections are stacked, but this one isn't. it would make more sense to stack these as well
00:59:841 (8,9,10) - this section makes more sense having the triples spaced out a bit because it's the kiai
00:10:555 (1) - same problem from the normal with the spinner over nothing, but this time at least it ends at the right time - should still probably just be a circle though
00:27:698 (1,2), 00:34:555 (1,2) - these two places and a few others the singer uses a different rhythm than what you mapped, it's on the blue and red ticks like this:
00:02:841 (2,3) - same rhythm
00:48:270 (1,2,3,4,5) - this gets the right rhythm, but is difficult to play because you haven't introduced that rhythm yet. if you do a repeating slider for the first time or times you use that rhythm it will become more obvious what you need to do for that section
01:24:270 (1) - could be a bit longer
insane: the big problem that i had is that a lot of the object placement choice seems "weak" - i'll have to write quite a bit to explain this, but i'll try to keep the lenght down a bit.
there are a lot of things that go into designing what kind of objects you use and how you use them. generally pretty good at chosing objects based on the timing of sounds.
there's also the type of sound - a lot of really high-difficulty songs, particularly crazy electronic music, uses strange slider velocity changes or shapes for strange sounds. since this is just a normal song and doesn't have really weird sounds you don't really need to worry about that
another thing people worry about is how they place objects. in some places you do this really well, like this stream-and-slider combination: 00:12:270 (1,2,3,4,5). sometimes people space apart more intense parts of the song more than calmer parts of the song, which you do pretty good too - 00:08:412 (4,1,2,3) is calmer and has easier-to-play spacing than 00:58:770 (2,3,4,5,6,7,8), for example.
but, there are more advanced ways of using this idea. for example, this section right here could use a more special type of spacing to make it more accurately follow the music: 01:15:698 (1,2,3,4,5,6,7,8)
there is a drum sound on 1, 3, 6, and 8 but not on 2 or 7. a lot of mappers would increase the space before you are clicking on a sound that has a strong sound like a drum beat on it.
i can't tell if you tried to do this or not, because the spacing is slightly different, but it's not different enough to really have that really strong impact on the drum sound that would influence the player's experience. look at the difference:
that's just one example where you could change object placement slightly and it would make the map feel much more closely related to the music
there are a load of other ways you can choose to emphasize things, but this suggestion alone, make the circles with the drum beats on them further away and the circles without them closer, is going to require a lot of change and i don't want to overload you or force you to start mapping too close to my own style
general things for the same map:
00:02:841 (2,3) - again these are off by a half a beat, they should be on the red tick before, not the white ticks they are on now.
00:10:555 (1,1) - i now see what you were trying to do with the spinner in the normal difficulty - i think having the spinner is a mistake because the silence shouldn't be emphasized in that way, but you should keep the circle
00:30:912 (7,1) - you use this "circle on slider end, then go back to slider head" thing a couple of times, and i often like it, but i feel like having it in this map is a bit too difficult to read and technical for the map, consider making it a regular circle not placed at the tail end of the slider.