Now that I've finished the original trilogy and I have a fair understanding of what's going on in Tools of Destruction, I think I'll start rambling on these forums.
So, I'm here talking about Ratchet's character, and compare his past self, to his current self.
Let's start with the first game, Ratchet's just a guy minding his own business when suddenly he as to save the world, not like it's his destiny or anything, he was just the guy that happened to be there, therefore he's an ignorant jerk always being selfish because he thinks that, as he has to save the world, he's the ruler of everything. But then come the big guys and he realizes that he's just some random mechanic that doesn't know anything about the galaxy.
In Going Commando, Ratchet's recruited by Fizzwidget, in Going Commando he's just a guy taking orders from his boss, later down the line when he meets Angela, he starts working with her, but he's still the sidekick, not the leader.
Up Your Arsenal, this one is pretty much the same as Going Commando, Ratchet's the guy that does the field work for the Q-Force, nothing more, Qwark and Sasha give him orders, it was very rare the occasion where Ratchet was like: "Oh man, this planet is in trouble we shall help them, I don't care for Sasha cause I'm the main protagonist!"
And now the Future series… Ratchet does EVERYTHING in Tools of Destruction, Clank tells him Talwyn is in danger? NOPE, Ratchet ignores him until Clank begs for him to listen to him. There's an incredibly harmless asteroid that belongs to the pirates? Ratchet goes destroy it just to be a d*ck. He's the one that makes decisions, he's the one responding to other characters and giving his thoughts on the matter. He's the one that's the leader. The others are just insignificant to the story, except for Clank and Qwark in some rare occasions. Ratchet is the equivalent of Chuck Norris in Tools of Destruction.
Granted, I still haven't finished it, but from what I can see, I'm not that far from beating it.