Hey there,
you speak about bias and then you tell us that we should buff Weaponary sura because it is your favorite, thats a bit tough to understand.
Just because you personally like it the most, that doesnt mean its supposed to be the best in everything. In fact, if its the best in everything that means the balancing has failed and it needs to be adjusted.
Besides, you said Weaponary Sura only has 2 Damage Spells while in fact they have 3 and are the only class with having an active debuff other than the pretty useless Slow effect or Poison which anyone can apply.
On top of that, they can also use 2 Weapon types as they are literally the only ones with a special kind of Sword.
Assassins are literally useless in PvM other than Bosses if you compare them to Suras or Warriors, killing Metins takes quite a lot longer.
Suras can do absolutely everything just fine, but ofcourse they also have weaknesses which in their case is the exact same thing Assassins excel in, bosses.
But unlike other classes, the Weaponary sura also excells at one thing when it comes to runs or bosses... tanking. Ofcourse theres one class to beat Weaponary suras for that, the black magic sura, but who is going to tell me he plays a BM Sura in PvM ?
TL;DR
No Matter how we put it, weaponary sura is not in a bad position atall.
Neither in PvM, nor in PvP.
Especially not with S-Skills.