Sifting through the classes and their passive skills, I notice a strange phenomenon: Some classes have attack and casting speed passive buffs. 

Now, this isn't just weird because it's something that can be adjusted through animation frames or whatever else, but the weirdness hits when you realize that the classes that do have these passives either attack/cast just as fast as other classes, or actually slower. If you compare the attack speed of a kunoichi to something like a sorceress or a maehwa, you'll immediately realize that she has a passive skill that doesn't actually help her outside of using node war weapons and hunting matchlocks.

There are classes that have amazing passives, and still have a high attack speed like the Striker and his Howling Wolf(+10% evasion), Increase Grip(Ignore 30% Grab Resistance), and Mountain Aura(+20DP, +20% critical hit rate).
Compared to...
Kuno has Killer Training(+10ap and +10% evasion is good), and Shining Blade (+10% attack speed is weird).
Valkyrie has Fitness Training(+300hp, +20dp is good), and Noble Vow(+10% cast speed is weird)
Lahn has Zephyr(+5% accuracy, +10% attack speed is confusing), and Blooming Affinity(+150hp is modest, especially for an assassin).
Hashashin has Pilgrim of the Sand(+20ap, +10% attack speed is less weird), Seer of the Sand(+150 MP, +300 stamina is very useful), and Ruler of the Sands(Stamina doesn't run out in the desert while sprinting, and increased desert illness resistance are a silly gimmick). I consider Hashashin to have modest passives.
And the attack/casting speed passives aren't even the weirdest ones I found.
Nova has Quoratum's Vigor(+45 HP recovery stat is the single most useless passive I have found), and Quoratum's Aura(+300hp, +20dp is good)

This isn't a complaint about Striker being given special treatment, just a suggestion that maybe some classes with worthless passives should be given an extra passive.
In the case of the attack/casting speed passive classes, perhaps they could get their passive as a base animation speed increase and a new passive skill, or even just a new passive skill altogether. Nothing as powerful as "Ignore grapple resistance," 
but something useful like more DP or accuracy or movement speed. At least with movement speed, the difference is noticeable, except again in the case of striker who has the ability to self-buff his movement higher than most classes can hope to reach.

These are only off-the-cuff suggestions, of course.

I don't think any class should have the burden of an "attack speed" passive buff. It feels hokey, or poorly planned: an afterthought to a class that isn't liked as much by the development team. Give us something more, but don't take away the attack speed, because then we'll definitely be slower than the classes that don't have attack speed passives.
I understand that altering classes's passives can mess with the current game's "meta" and "balance," but then there are classes with amazing kits and amazing passives, so that argument is self-refuting. No class's kit is so overpowered that it warrants them having only one passive.

Thank you. 

Looks at my classes passives and dies from sadness

Imagine complaining about one of the strongest passive, while some classes got passives like increased mana lmao

Any class passive that isnt straight up resistance, resistance penetration, DR, evasion, or accuracy is worthless because of what you stated already where they can just adjust the damage and speed or skills, the stamina costs of skills/what skills regen stamina, or the base running speed of a class. Even HP is worthless because they can just adjust the HP you get per level like what they did with zerker getting 2x the amount of every other class per level. Hell even DR is useless in capped nodewars.

Someone made a forum post a while back where they basically said "have all the available passives opened for every class and let the player choose" which would be way better since the devs are so out of touch. I think that would be fun and a little more fair even if it would have its own issues like archers getting attack speed.

You are not exactly right since they can also adjust class DR, eva, accuracy just like they can with HP etc. In fact there are classes with significantly higher base eva than other classes like ninja or higher DR like striker.

yeah but you are wrong in the fact you don't get base evasion or accuracy you get percentage evasion and accuracy from literally every passive in the game xD you can't directly change percentage evasion without buffs. And yes before you ignorantly say "well every % evasion is X flat evasion!" Not how that works hence why caps have a different number for percentage and flat evasion. 

% based evasion and accuracy simply gives as much eva/accuracy as the similar amount of evasion/accruacy gives ie.: 5evasion equals with 1% evasion etc. At least that's what bigandshiny tested, I personaly not double tested it, but garmoth also uses this as reference and noone tested it as otherwise so far.

You arrive at this unhinged point, yet mostly truthful, that class passives are entirely meaningless (for the most parts).  As a whole, attack speed and cast speed passives don't do anything because if for any reasons the class felt too fast, it would have been nerfed anyways. Just for instance, Awakening Witch has a 10% passive and is able to grant herself a 20% cast speed boost from speed spell. Yet, she's still very slow.  More to the point too, she technically has +20 magic AP along with +12 AP through passives, yet it doesn't mean her damage is massive insane.

Imagine having a +20 magic AP passive, but getting the overall damage from class mods reduced by 5%. It's just a zero-sum game. 

There is however some caveat to this point of view. It seems that some classes have passive elements that they just do not deserve. Back in the days, addons were locked from class-to-class and from skill-to-skill. Meaning that you had to play with what was given to the skill. Dark Knight for instance had addons (if I can actually believe what some dk told me) that were +20 AP for 5 seconds along with other. Those were definitively NOT accounted for in terms of balance, which contributed to Dark Knight hyper dominance. Some classes addons were just laughable compared to it such as 5 PvP AP for 5 seconds at best.

There are some things that are just not looked at. Sage have ridiculous buffs (read passives) that are available to them. The most appaling for me being the +20 DP for 20 seconds on their Q block. Recently, Awakening Witch also received a +20 dp on their Q block in exchange for the +20% all resist, but the duration of the DP buff is 5 seconds. 

TL;DR  Passives are usually pointless, and when they matter, they are a problem. I just can't get myself to say that they should be removed all together, but maybe they should.

Imagine not having +20AP or +12AP passives but also have even more reduced damage from class modifiers...
Also you are not even right. The 20AP passive is one of the strongest one in the game, you literately get as much stat as a whole accessory gives you.

You linger merely on an example. 
It's just a logical argument I try to give. Give a class a 100 AP passive. Then whoops! It seems like the class deals a lot more damage than it is meant to. You then reduce the damage elsewhere. It's just appearances. I don't see in what world you'd think that Awakening Witch for instance deals 32 AP worth of damage too much.

Cast + Attack speed and damage passives simply are the most monitored stat in the game. Defensive and Evasion / Accuracy passives get swept under the rug a little bit more.  But cast and attack speed passive really earn the gold medal of useless passive. There's no world where I believe Kunoichi, Musa, Witch WIzard, Warrior's attack speeds are wildly different than the other classes.  These passives more or less act as light resistance against cast and attack speed modifiers (because base speed is lower, %modifiers effects are lesser), which is FAR from what one might consider at first glance when looking at said passives.

Of course, you're free to believe whatever you wish to.

If you told me give a +20 melee AP passive to Striker out of the blue, I'd also say it's a very strong passive, perhaps the strongest one. Because I believe in Pearl Abyss incompetence these days to let that slip with no further adjustments. The Witch and Wizard +20 magic AP passive went through almost 7 years of adjustments and probably more given alpha or beta adjustments I have no knowledge about and has always been considered in the balance perspective. Except perhaps during the Succ Wizard Meta, Succ era being a chaotic time for balance.