What stat effects the Sword Saint abilites?

[VeloZer0]

It's a little complicated. Overall Ninja is generaly considered the best class to level up as. Ninja's have the best speed growth and some of the highest strength growth in the game.
These numbers are part of a formula that won't make sense unless you are really interested in mechanics, but you can use them to compare. The lower the number the better the stat growth.
P(Physical)-Attack:
Mime: 35
Meliadoul: 39
Knight: 40
Lancer: 40
Cloud: 42
Orlandu: 42
Ninja: 43
Samurai: 45
Monk: 48
Beowolf: 48
Agrias: 50
Speed:
Virtualy every class in the game has the same growth for speed (100), with the exception of Thieves(90) and Ninjas (80).
M(Magical)-Attack
Every every generic class in the game with the exception of Mime(35) has the same M-Attack growth (50). (Which is really stupid) The only specials that are exceptions are Cloud(46), Beowolf (45), Orlandu (42) & Ramza (48).

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Conclusions:For those who just want to be told what to do
Level up as a Ninja. It is the only class with good speed growth, has P-Attack growth almost equal to all the highest classes, and M-Attack growth doesn't really change depending on the class you level.


Fun Fact: Orlandu has higher M-Attack growth than any of the spell casters, but his P-Attack growth is overshadowed by both the Knight and Lancer.

EDIT: I spent so much time looking all this up I forgot about your first question.
All of the skills you mentioned are physical except for Beowolf's Magic Sword abilities. Both Attack Boost and Arcane Strength increase damage by 133% in most cases.
The bigger key for maximizing the success of Beowolf's abilities is his Faith stat. Magic spells are multiplied by the Faith stat as a percentage, so if you stick with the ~70FA he starts with the spell chances for success will all be multiplied by 0.7
WARNING: Do not raise any character's Faith above 94, they will leave your party perminantely and forever. No joke.