General: Strongly consider moving the offset by about +20 on the 00:48:071 - since the beats seem to be happening in the map earlier than in the song. I've noticed like everywhere if i put it on 25% speed. I cannot do this because this is the exact same mp3 used in the current two ranked mania sets.

The bg has 5199 kb/s which is a lot, more than the audio lol. Dunno but transform it into jpg somehow, it will take a lot less space.It's a bit unnecessary because the folder size is still reasonable. I like the really high quality BGs ;p

Entrance to Valhalla

I kinda stand by Mir for this, except I think you don't need to sacrifice the symmetry concept, you'll just need to put in a bit more effort and possibly limit your design so that the map will be more consistent in terms of spacing. So to put it out again, I think that your overall spacing is raised too much therefore musical parts that need emphasis lack it on comparison to others, while on the other hand, the forced symmetry made certain patterns inconsistent when it comes to difficulty and emphasis. So firstly I'd like to discuss the emphasis idea implemented about the overall spacing, while on the second part i'll discuss how i think you can make stuff more consistent while preserving the symmetry etc. As I said to Mir, the only reason this would be something of discussion is how you treat spacing versus emphasis. In the case for my beatmap, the difficulty threshold is intentionally raised and this song has very little room to improve difficulty outside of spacing, therefore, concrete patterns are used at the risk of having 'awkward playability' to achieve my concept of symmetry, which of course regards to my high spacing. The spacing emphasis we're so used to seeing is not optimally captured because it wasn't intended to be captured in such modern ways. You will have one pattern on one half, and then play another pattern on the other half. The transition from patterns can be argued for both sides, I chose a side that's not seen in modern era. In addition, this song is a KAC Contest Song Winner and was one of the most difficult charts in SDVX and I like to reflect the difficulty this song presented in SDVX but for osu. It's what I do with all my other Contest Song Winners (iLLness LiLin, Lachryma, Celestial stinger, etc).

00:54:071 (1,2,1,2) - So in this section you gave larger emphasis to 00:48:889 (1) - these NCed notes that have this loud synth which other notes do not, but in the 1-2 ones, the (2) which doesn't have any important synth in this pattern particularly i initially linked is as emphasized as (1)? Why don't you keep that consistent https://i.imgur.com/ucfBFer.jpg with something like this. You will keep the symmetry idea while also make the (1)'s which sound stronger emphasized as you do often(dont mind the bg, i cant evaluate your map on bright bg xd). You can look at the top right and see where the objective spacing is in terms of pixel relation. The thing you linked me at 54s has more spacing than what was linked at 48s, and there is a clear finish on the former which is why I have the larger spacing. The two triangles from before don't have anything interesting as they are composed in 1-2-3 but the latter is composed in 1-2 1-2 so, I only reflect that. Your suggestion for keeping symmetry seems okay too, reasonable suggestion. I dislike it because it interferes with the former triangles. I wanted the spacing to be fill in the upper half while keeping a design since I already had objects in the bottom half. It's something I like to do in all my maps.
00:55:707 (1,2,3,4) - Since this is a lot more intense with those loud af sounds I think you should make it harder and different than the previous patterning since its not the same? How about something like this https://i.imgur.com/jlMQC4w.jpg I don't see any good in blending in such different sounds with same kind of patterning, it deserves special emphasis tbh. I thought about something like this too, the reason I didn't like it is because of the visual aspect yet again. There are objects in the bottom, then objects near the top, so I wanted to finish the section with objects in the center while keeping to "some" sort of symmetry. The triangle makes sense to me because the distance spacing is larger in whole than the rest of my previous patterns. I used flow change here because of the finishes. Your suggestion is reasonable too, I prefer my way because it achieves more of my vision.
01:03:548 - Not related, but I think you should map this, its quite audible and i think that the stream should start on the red tick. You're right here, I added more to the stream.
01:25:980 (1,2,2,3) - These are particularly overspaced, especially that slider which is not even a synth. https://i.imgur.com/r5wvgvq.jpg By reducing the spacing similar to the picture, 01:27:343 (1,2,3,4,1,2,3,4,5,1) - this pattern which truly sounds much stronger will get the emphasis it deserves. Currently their jumps are actually similar to the distance of the ones I was talking. I've read your reply on Mir's point but having actual mechanical impact with spacing as differentiation is felt much more strongly than simple placement. Also density is not really something that emphasizes this pattern because in the map your note density is pretty high so it won't truly stand out in comparison to the rest. The repeating pattern is quite obviously distinguishable from the rest because it, repeats (and stacks)... The spacing on previous objects is at 2.60 while the spacing on the later repeating pattern goes in and out of 2.90 because it moves a bit up and down. I don't disagree that reducing spacing can help 'emphasize' the later pattern but the later pattern is already quite obvious in itself that it's different and the pattern itself is enough to be 'emphasizing' because of how different or impactful and especially how active it plays compared to the circles I placed before which was just more or less moving around the map, not so rigid with snapping and intense 1/2 clicking. I also can't agree with your suggestion because I find it a bit unnecessary to apply for the reasons I stated above. If anything, I think this is nitpicky so I stand neutral on it, leaning more towards disagree for my reasons.
01:42:071 (1,2,1,2) - Identical concern as I've mentioned earlier to 1-2 patterning. The (2)'s are quite weaker than (1)'s yet they have similar or even higher emphasis in spacing (01:42:071 (1) - clicking on this you can see 2.7x previous and 3.6x next). By doing something like this https://i.imgur.com/l55fzcI.jpg you will make the emphasis on (1) which is a strong synth consistent to 01:42:616 (1,3,5) - for example where you give emphasis to synth, preserve the symmetrical structure, and keep overall intensity of the jumps high. This kind of suggestion goes to all 1-2 jumps in the section, your choice how you build them.
Also regarding the 1-2, in this section imo they should be noticeably less emphasized than in 01:49:161 - this section where the sounds are the same but the intensity of the section scaled overall, which means that they should be scaled appropriately to the new similar, but more intense section. Your suggestion makes good sense here. I did try to work with this idea, but I couldn't find a way to keep my visual aesthetics this way because I try to avoid overlaps with previous existing objects and make use for further objects. I did however fix some of my gradual spacing idea and fixed some back and forth patterns to be consistent with my intentions. Had to adjust some directions but I think it's a little bit better now~
01:52:980 (1,2,1,2) - Even though these sounds are intenser than 01:50:798 (1,2,1,2) - the large spacing difference won't compensate for the patterning. You should imo make this more emphasized than that in spacing at least. My previous suggestion of 1-2 patterning goes to here too also tbh. I mean, you could look at it in two ways: the pitch is higher so make the spacing higher. or: the pitch is different so that pattern is treated differently. The spacing isn't the only thing to look at here because you should factor in how a player a plays this versus the back and forth stack from before. One is simpler than the other, one is less active than the other. The pitch rises and the gameplay is more 'exciting' whereas the previous has something that's flatter as it is with the music. What I like about my current patterns is that they can flow visually well into one another while keeping to my symmetrical idea. But the interpretation is quite open and I think it comes down to what you prefer more, many people will say different.

Now regarding the symmetry individual emphasis inconsistencies:

00:50:116 (2,1) - The (1) which is the downbeat is less emphasized than 00:51:071 (1) - because of spacing. I know I know patterning etc, but look, there's no harm in making it emphasized by spacing too. An option I found to be quite ideal was making the previous pattern https://i.imgur.com/IFzei4I.jpg like this, making the circle on the left being far away from the (1) therefore making the jump as about large as 00:50:934 (3,1) -. You can do it in a similar way here https://i.imgur.com/Jz0hhZx.jpg . In this pattern consider bringing 00:52:434 (1,2,3,1,2,3,1,2,3,1,2,3) - closer to the middle to make it easier, I mean, 00:53:116 (3,1) - just look at this jump on this relatively calm section, it's just a regular beat but this is 4.30x compared to a downbeat 00:52:434 (1) - with a finish. I'm glad you can understand my point of view. Your suggestion doesn't fit me will, and there are many ways to try and map this as shown in other difficulties. As I state before this map is conceptual so, modern mapping techniques will be quite loose and it's due to the symmetry. Because you can understand my reasoning, I don't want to expand too far in it. Gradually getting spaced is the idea while pertaining to symmetry and not everything can be as "optimally emphasized" as you wish because of symmetry. My idea with triangles and rotations etc.
00:54:616 (1,2,3,1,2,3) - I believe you should put in a little more effort here to make (1)'s emphasized like you do usually, this is just a large inconsistency without any particular reason. Simply just copy paste the right triangle and invert it https://i.imgur.com/IQdKwqs.jpg idk, the angle compensates for the lack of spacing to the nced note. Okay, I fixed this. I think I had a reasoning for playability but the inconsistency is much worse, so I did fixed the circles there.
01:49:844 (3,1) - This is one of the spots in which it will take you effort to arrange the patterns so that it gets spacing emphasis like most (1)'s do. https://i.imgur.com/blyyqCm.jpg idk? I do this sort of thing quite consistently as shown here 01:52:025 (3,1) - and 01:52:844 (3,1) - so,
it would be a bit jarring to fix one and not the others but they're all kept to being consistent with sharing the patterns together. The only (1)s that get obvious emphasis are the (1)s that go back and forth stack on each other. While your suggestion isn't bad, I don't see it being a huge necessity. There are a lot of ideas that work here don't get me wrong.

Thank you for your suggestion MaridiuS. Thank you for spending the time to write this all out and provide visual examples of your sentiments as it makes it easier for me to see what you mean. While I cannot agree to fix on a lot of what you've suggested, I hope my reasonings make sense to you. I only applied what I saw fitting and beneficial to my map. This took me a while to evaluate so please don't be offend if my response came off negative.