Haa, yeah. I'm not too fond of Takahashi's stuff myself.
As for Shiro summoning Saber by accident... well, it was only accident on his part, really. His personality, combined with the fact that he had in his possession (in his very body) an artifact belonging to Arturia, pretty much guaranteed that he was going to end up with Arturia as his Servant.
Possessing an artifact belonging to a particular figure, or otherwise relating to them, gives one a much-increased chance of summoning a specific Noble Soul.
Example: The Einzberns used a stone slab from the temple of Heracles to ensure that they'd get Heracles. They wanted him specifically because his fame is known worldwide, and his legend was as a nigh-invincible warrior of immense power.
edit: I suppose Shirou might accidentally end up summoning Black Saber, if you're dead set on the "evil Servant" idea.
Another thing that can affect a Servant's power is where they happen to be at the time. Having the "home turf advantage" really counts for a lot with Kinoko World's magic system, especially with Noble Souls.
Sasaki Kojiro would've been even more outclassed anywhere other than Japan, whereas Medea, Medusa, and Heracles would've been stronger had the Grail War been set up to take place in Greece instead. Similarly, if the Grail War was held in the U.K., Arturia and Cu Chulainn would have been h4x. (The hero EMIYA wouldn't get a boost anywhere, since his legend hasn't happened yet.)
Dunno about Gilgamesh. Perhaps, since he claims all the world as his own, anywhere he goes is his "home turf".
(I'm not gonna touch on the Luca Blight one. That's just wrong, man. :snigger: )
As for Shiro summoning Saber by accident... well, it was only accident on his part, really. His personality, combined with the fact that he had in his possession (in his very body) an artifact belonging to Arturia, pretty much guaranteed that he was going to end up with Arturia as his Servant.
Possessing an artifact belonging to a particular figure, or otherwise relating to them, gives one a much-increased chance of summoning a specific Noble Soul.
Example: The Einzberns used a stone slab from the temple of Heracles to ensure that they'd get Heracles. They wanted him specifically because his fame is known worldwide, and his legend was as a nigh-invincible warrior of immense power.
edit: I suppose Shirou might accidentally end up summoning Black Saber, if you're dead set on the "evil Servant" idea.
Another thing that can affect a Servant's power is where they happen to be at the time. Having the "home turf advantage" really counts for a lot with Kinoko World's magic system, especially with Noble Souls.
Sasaki Kojiro would've been even more outclassed anywhere other than Japan, whereas Medea, Medusa, and Heracles would've been stronger had the Grail War been set up to take place in Greece instead. Similarly, if the Grail War was held in the U.K., Arturia and Cu Chulainn would have been h4x. (The hero EMIYA wouldn't get a boost anywhere, since his legend hasn't happened yet.)
Dunno about Gilgamesh. Perhaps, since he claims all the world as his own, anywhere he goes is his "home turf".
(I'm not gonna touch on the Luca Blight one. That's just wrong, man. :snigger: )