I decided to make a fighter subclass with a friend of mine and am looking for feedback on things to change, add, or remove to make this more balanced. It doesn't feel quite right.

https://www.dndbeyond.com/subclasses/1247589-weave-breaker

Each Homebrew Subclass has a pattern in their creation, since this is a fighter subclass, luckily for you I have the formula for creating homebrew subclasses for fighters. And yes there is indeed a few problems with this homebrew subclass, no there is something wrong with this subclass, I just can't put my finger into it though as well.. But first here is the formula for creating a fighter subclass by feature.

3- introduce the base of the subclass with some sort of resource cost (DoT which you can do X times a short/long) + perhaps a small fun RP element like a skill (medicine?) 

7- usually is a RP/ non-/ little damage consistent ability (determine an enemy's strength, can get double the healing from spending hit dice/ can treat a 19 as a 20 on a death save, something like that) 

10- improve 3rd level base (can ignore resistances to necrotic or whatever the DoT is) 

15- minor resource improvement for base 3 or 7 

18- key mark ability. make it do something cool because rarely anyone gets here

each class follows a formula, and this is an example of the fighter's breakdown

Weave Breaker

Interesting concept as it utilizes an already existing lore in dnd, simple and neat. But there is a lot of features. Rating 9/10. Only one feature needs proper clarification on what it does and why its used which is Anti-magic Dice.

Anti-Magic Dice

Scales via the brute's damage dice table concept, does not have any other descriptors that describe what it is utilized for except in another feature where it is noted in Anti-Magic Ward, Aura Breaker, and in Mana Wrack in which there are a lot of 3rd level features to note off, it needs more explanation on why it exist, why and how it can be utilized, and what is its limitations asides from adding an additional dice in simple and short descriptions,  also suggest that this should have a use limitation like the psionic dice of the Psionic warrior equal to double proficiency bonus, however this can be the base feature for 3rd level. Rating 5/10.

Anti-Magic Ward

Can scale at higher levels, works as having resistance against magical effects which is extremely strong yet rewarding as a subclass. 

Minor Magic Ward - works well with its reactions.

Lesser Magic Ward - change this to resistance against spell damage in general but only against one damage per turn, (your choice) for nerfing purposes unless you want it to have resistance against spells. This is something given at 10th level after all and it does well with the scaling specially if your playing a magically resistant race.

Greater Magic Ward - Extra damage?! good feature makes senses as a 18th level feature.

Uses per proficiency bonus, that's usually an okay scaling for an ability for this.

This is a great scaling ability but maybe should follow a single resources from the Anti-Magic Dice pool of twice proficiency instead? This is also a suggestion. Rating 7/10.

Aura Reader

Works like a Paladins detection but for magic spells and is similar to the fighter battle masters 7th level Know Your Enemy. This is fine as it reveals only one thing from the enemy at this level but it needs limitations on how many times you can use it like the anti magic ward but that may be to much to count on, in addition it scales well with how many you can use but. Though it does work as a concentration so maybe make it like having to be need to concentrate on as it grants an automatic revelation of spells slots and spells, but that is your choice and the concentration idea is actually terrible in hind sight. So I suggest you make a clarification on the limit for how much times this can be utilized. Maybe have it work like hunters mark spell so it can have an effect. However with the amount of features already here at 3rd level, I suggest making this as a replacement feature for Aura Breaker but that will have to redo the entire subclass. So since this seems like to much features at 3rd level, you can either change this into a 7th level feature instead and have it work like the Know your Enemy of the battle master with more info and an amount of times it can be used via spending the Anti-magic dice as base from that resource pool possibly but that will be quiet the strong ability so it having three uses at set levels is pretty decent for its scaling, the reason as to why I am suggesting to change this to a 7th level feature is because you gain a lot of abilities already at 3rd level. Rating 8/10. fits what the subclass is meant to be.

Mana Wrack

Works like the blood hunters Brand Of Castigation, you should probably gain inspiration from that and use it instead as your base though make it a little stronger as this is the 10th level feature. It already works well for its class so I don't think any changes are need except that in needs limited uses of once at 10th level and then twice at 18th level. 7/10.

Hole in the weave

An interesting twist to the ability usage overall works like a wild magic antimagic field spell but with one use determined by a roll of a dice, no needs any changes its balanced this way already that it is either a hit or miss that is either worth or not worth the risk of failing the BBEG's power word kill spell. Rating 7/10.

Master Aura Reader

An minor resource improvement overall does not need any changes. Rating 8/10.

Mana Crush and Greater Anti-Magic Ward

Has a feature name error off Mind Wrack instead of the feature above stated to be Mana Wrack. Change the healing equal to Con modifier regeneration when hit points are at half health instead as you don't want to overcomplicate the healing from damage of a 120 plus damage right? or not this is really good. Rating 7/10.

Overall this subclass only needs proper formatting and clarifications, simplifications, and such for the features which I think you provided enough. The reason why I think that you think that there is something wrong is because there is a lot off features that this subclass give that may be strong. Magic Resistance is a hard thing for me to personally scale but I generally know how strong it is to some extent. That's why it felt so odd as well even for me. I suggest you make the resources pool based on the Psi Warrior if you want but this is pretty good in general. Overall Rating 8/10. Strong and fits its roll too much actually.

Also for the Anti-Magic Dice use a google docs and make the table there then paste.

There's a lot going on here. You've got six different features and half of them upgrade for a total of 11 discrete upgrades. That might be part of what feels off - there's just too many moving parts.

I'd probably drop Mana Wrack/Crush to give everything a bit more room to breathe. The whole "healing from hurting enemies" thing feels a bit out of place with everything else, so I think it would focus the concept a bit more while also reducing the complexity.

I'd also take another look at Aura Reader from the perspective of what actionable info it gives you. As far as I know, you're not going to actually treat a Charisma caster any different from an Intelligence caster, and knowing highest spell slot just seems like a roundabout way of asking how strong the creature is, which feels both meta-gamey and too late to matter since you've already begun combat. Ideally, Aura Reader gives you the information needed to apply your other features. Between that and the flavor around the concept, I'd see Aura Reader more like an area-wide "detect spellcaster" effect where you identify anyone who can cast spells within x feet. Then perhaps you can still mark 1/2/3 of those for AB.

Also for Hole in the Weave, it seems a bit much for you to be able to reject the casting of an entire fireball - yes they could move it, but with good positioning you could effectively block all of the valid areas for a larger spell. I'd say for an area spell, if the spellcaster fails the check then the spell goes off as normal but your square is exempt from the area. It also doesn't feel like it should be a constitution save for them to successfully cast magic, their spellcasting ability would be more appropriate.