Heya, you can thank ezek since he showed this set to me
General
Having custom hitsounds for sliderticks is usually considered a bad thing but having a loud sound that emphasizes the middle of a slider is extremely irritating for anyone who is playing as there is something that you bring up as important enough to be hitsounded but not important enough to be mapped and after considerting that you are using the exactly same hitsound for beats that are mapped normally, i can not see anything about these hitsounds that would make the map better in any way. After inspecting the map for a while i can see that your map is mostly following the synthesizer through rhythm choice so i think it would be much, much better to emphasize that you are indeed focusing on those and just leave out the hitsounds completely (and possibly changing the slider tick rate to 1 to support this) as bringing up stuff you do not really follow when they are not supported by the basic rhythm in any of the difficulties above easy
Tags : sans the skeleton frisk character i really don't see a point in these tags. They do not really connect to the song itself and do not really help anyone to find this song (they'd basically search for sans or undertale which are already covered), sans_the_skeleton with the underscores would be sorta fine as it would be the name of the character but frisk or character don't really make sense. Though you might want to add some tags : radiation as that is one of the aliases toby uses (and most of the ranked undertale maps have it in the tags), chiptune the "real" genre of the song and soundtrack as some people search for that instead of "OST"
Easy
Having ~1.5x DS battles with the general idea that the speed the players move from object to another would match the speed of sliders to create mapping that is really easy and simple to follow which is kinda what easy difficulties should be about.
00:15:000 (1,2,3) - Aesthetically speaking it'd look nicer if the sliders would both be equally far from the hitcircle
00:37:500 (1,2,3) - This is quite a sharp angle which kinda makes the pattern look quite tightly placed. Imo a more "perfect triangle like" pattern would work better https://puu.sh/xuTuo/b69db9551f.png
Normal
I do not know have you noticed this but some of your stacks make the spacing really inconsistent. You can compare the highest spacing i found against the lowest 00:05:625 (1,2) - 00:20:625 (1,2) -. I would not be too concerned about the stacks that are increasing the spacing as they mostly feel exactly the same as any other stack but i would be concerned about the ones that notably decrease the spacing as they create overlaps 00:09:375 (1,2) - 00:11:250 (1,2) - that you are most likely trying to avoid with the high DS in general
00:18:750 (1,3) - 00:27:187 (3,5,6) - I don't really feel this kind of small and possibly unintentional overlapping is good for the structure either
Advanced
Since you are mapping an advanced (which is supposed to have aspects from normal and hard level difficulties) that has relatively similar rhythm when compared to the normal, you could spice up the rhythm by adding a bit more clickables here and there to match the synthesizer such as mapping this 00:07:968 - kind of beats or making a triple 00:18:281 (3,4) - here
00:00:937 (3,4,1,2) - and 00:05:625 (1,2) - are quite different from any other pattern in the whole difficulty as they have extremely loose flow. Most of the time your mapping makes great and sense-making patterns but i just do not think these two are really on that level. By loose flow i mean stuff like all of the objects in this 00:00:937 (3,4,1,2) - pattern try to create their own circular flow while all of the other objects fail to follow that. If you don't know what i mean i can visualize it for ya, just ask me
00:20:390 - 00:42:890 - Add a hitcircle for the consistency with literally any other pattern in the difficulty 00:12:187 (3,4) - for ex.
00:43:125 (4) - NC?
Hard
OD 7 is pretty high generally for hard difficulties, would recommend 6 or 6.5 (preferably 6). AR feels a bit high aswell and i would use 7.5 or 7 for hard difficulties generally. Right now it looks more like a low end insane rather than a hard diff stat wise
The rhythm feels really awkward for a hard. I thought the highest difficulty would generally use nearly everything the song offers to create an enjoyable experience. Imo currently this is really lacking on the "using everything" part time to time as stuff such as 00:04:218 - this kind of stuff happens constantly where you pretty much ignore a really strong beat (well not exactly ignoring but not giving it appropriate emphasis through rhythm choice) while you have mapped many many similar beats 00:04:453 (2) -pretty much "normally"
Since this is a hard you could consider stuff like spacing emphasis or atleast spacing stuff so it'd follow the song. 00:08:906 (1,2,3,4,5,6) - I'd say this is the clearest pattern/melody that could use it. Simply the synthesizer changes on the 4 into much higher pitched notes when compared to the two first notes so you can basically divide that one pattern into two sections that are actually following different type of things 00:08:906 (1,2) - 00:09:375 (3,4,5,6) - (included 3 in the second synths as it's a strong beat). Considering that i do not thing it's a good idea to use similar spacing for those two nor is it a good idea that they are in the same pattern. For example i would use this https://puu.sh/xvqtU/35e417c898.png kind of patterning to show off the change of strength and beat pattern through spacing and patterning, Though i'd be more than happy if you would come up with your own pattern but that is there as an example
Continuing on ^ 00:12:890 (4,1,2,3,4,1,2,3,4,1) - for example here it makes more sense already but start the bigger spacing from this 00:13:359 (2) - as it is the first notably higher note. Also it would be consistent with other similar beats spacing wise (The 3 and 4 for example 00:13:359 (2,3,4) - )
00:19:687 (4,5) - Sorta appropriate 1/16 usage, good job fam. It doesn't feel painful to play even on DT
00:44:300 (1,2,3) - I just feel like the spacing gets too high here considering you most of the time use spacing that is barely above 2x but here it gets nearly up to 3x. Yeah it might be the final pattern but the melody does not change like that but rather stays relatively similar to any other part of the song
[]
I think this should be pretty much ready to go but i'd highly recommend considering making the rhythm bit harder on the advanced and on the hard as it would make the spread make more sense overall and make the difficulties actually stand a bit better for the difficulty level you are portraying through the name choice
Other than that, best of luck to you!
General
Having custom hitsounds for sliderticks is usually considered a bad thing but having a loud sound that emphasizes the middle of a slider is extremely irritating for anyone who is playing as there is something that you bring up as important enough to be hitsounded but not important enough to be mapped and after considerting that you are using the exactly same hitsound for beats that are mapped normally, i can not see anything about these hitsounds that would make the map better in any way. After inspecting the map for a while i can see that your map is mostly following the synthesizer through rhythm choice so i think it would be much, much better to emphasize that you are indeed focusing on those and just leave out the hitsounds completely (and possibly changing the slider tick rate to 1 to support this) as bringing up stuff you do not really follow when they are not supported by the basic rhythm in any of the difficulties above easy
Tags : sans the skeleton frisk character i really don't see a point in these tags. They do not really connect to the song itself and do not really help anyone to find this song (they'd basically search for sans or undertale which are already covered), sans_the_skeleton with the underscores would be sorta fine as it would be the name of the character but frisk or character don't really make sense. Though you might want to add some tags : radiation as that is one of the aliases toby uses (and most of the ranked undertale maps have it in the tags), chiptune the "real" genre of the song and soundtrack as some people search for that instead of "OST"
Easy
Having ~1.5x DS battles with the general idea that the speed the players move from object to another would match the speed of sliders to create mapping that is really easy and simple to follow which is kinda what easy difficulties should be about.
00:15:000 (1,2,3) - Aesthetically speaking it'd look nicer if the sliders would both be equally far from the hitcircle
00:37:500 (1,2,3) - This is quite a sharp angle which kinda makes the pattern look quite tightly placed. Imo a more "perfect triangle like" pattern would work better https://puu.sh/xuTuo/b69db9551f.png
Normal
I do not know have you noticed this but some of your stacks make the spacing really inconsistent. You can compare the highest spacing i found against the lowest 00:05:625 (1,2) - 00:20:625 (1,2) -. I would not be too concerned about the stacks that are increasing the spacing as they mostly feel exactly the same as any other stack but i would be concerned about the ones that notably decrease the spacing as they create overlaps 00:09:375 (1,2) - 00:11:250 (1,2) - that you are most likely trying to avoid with the high DS in general
00:18:750 (1,3) - 00:27:187 (3,5,6) - I don't really feel this kind of small and possibly unintentional overlapping is good for the structure either
Advanced
Since you are mapping an advanced (which is supposed to have aspects from normal and hard level difficulties) that has relatively similar rhythm when compared to the normal, you could spice up the rhythm by adding a bit more clickables here and there to match the synthesizer such as mapping this 00:07:968 - kind of beats or making a triple 00:18:281 (3,4) - here
00:00:937 (3,4,1,2) - and 00:05:625 (1,2) - are quite different from any other pattern in the whole difficulty as they have extremely loose flow. Most of the time your mapping makes great and sense-making patterns but i just do not think these two are really on that level. By loose flow i mean stuff like all of the objects in this 00:00:937 (3,4,1,2) - pattern try to create their own circular flow while all of the other objects fail to follow that. If you don't know what i mean i can visualize it for ya, just ask me
00:20:390 - 00:42:890 - Add a hitcircle for the consistency with literally any other pattern in the difficulty 00:12:187 (3,4) - for ex.
00:43:125 (4) - NC?
Hard
OD 7 is pretty high generally for hard difficulties, would recommend 6 or 6.5 (preferably 6). AR feels a bit high aswell and i would use 7.5 or 7 for hard difficulties generally. Right now it looks more like a low end insane rather than a hard diff stat wise
The rhythm feels really awkward for a hard. I thought the highest difficulty would generally use nearly everything the song offers to create an enjoyable experience. Imo currently this is really lacking on the "using everything" part time to time as stuff such as 00:04:218 - this kind of stuff happens constantly where you pretty much ignore a really strong beat (well not exactly ignoring but not giving it appropriate emphasis through rhythm choice) while you have mapped many many similar beats 00:04:453 (2) -pretty much "normally"
Since this is a hard you could consider stuff like spacing emphasis or atleast spacing stuff so it'd follow the song. 00:08:906 (1,2,3,4,5,6) - I'd say this is the clearest pattern/melody that could use it. Simply the synthesizer changes on the 4 into much higher pitched notes when compared to the two first notes so you can basically divide that one pattern into two sections that are actually following different type of things 00:08:906 (1,2) - 00:09:375 (3,4,5,6) - (included 3 in the second synths as it's a strong beat). Considering that i do not thing it's a good idea to use similar spacing for those two nor is it a good idea that they are in the same pattern. For example i would use this https://puu.sh/xvqtU/35e417c898.png kind of patterning to show off the change of strength and beat pattern through spacing and patterning, Though i'd be more than happy if you would come up with your own pattern but that is there as an example
Continuing on ^ 00:12:890 (4,1,2,3,4,1,2,3,4,1) - for example here it makes more sense already but start the bigger spacing from this 00:13:359 (2) - as it is the first notably higher note. Also it would be consistent with other similar beats spacing wise (The 3 and 4 for example 00:13:359 (2,3,4) - )
00:19:687 (4,5) - Sorta appropriate 1/16 usage, good job fam. It doesn't feel painful to play even on DT
00:44:300 (1,2,3) - I just feel like the spacing gets too high here considering you most of the time use spacing that is barely above 2x but here it gets nearly up to 3x. Yeah it might be the final pattern but the melody does not change like that but rather stays relatively similar to any other part of the song
[]
I think this should be pretty much ready to go but i'd highly recommend considering making the rhythm bit harder on the advanced and on the hard as it would make the spread make more sense overall and make the difficulties actually stand a bit better for the difficulty level you are portraying through the name choice
Other than that, best of luck to you!