Really the prequel trilogy can be broken down into emo teenager whines and tantrums his way to being massive villain. So many missed opportunities with the writing of the Anakin to Vader" story.
Don't get me wrong, I can totally imagine a stroppy teenager with too much power going that way, imjust think it made for a poor story, poorly told.
Unless your of a certain age (and probably then in the same boat as me) you have no idea how gutted I was to wait all those long years to find out how Vader came to be and be served with that garbage.
Yeah, but, I mean...Vader was whiny. If not for having James Earl Jone's massively deep voice to offset the dialog, much of what we hear Vader going on about is basically whining. I mean, a bit less than Anakin, sure, but he's also 20 years older at that point, so...
For real, imagine Hayden Christensen with the lines...
"Where are those transmissions you intercepted? WHAT have you DONE with those plans?"
"I want that ship, not excuses!"
"There is no escape. Don't make me destroy you."
"That name no longer has any meaning for me!"
...etc
Whining is basically the same thing as threatening. You're demanding something with unpleasant consequences for failure. The difference is, Vader threatened with magic throat crushing; Anakin threatened to be more annoying.
The primary failing of his fall in the prequels is that he's never really given a compelling reason to go to the Dark Side; certainly not one that resonates with the audience. There's never the promise of power and the corrupting influence of getting what you want through (the?) force. Even the few bits he has like "Jedi are forbidden to love" come across as hamfisted and cliche.
But I think that's part of where the EU went off the rails, in assuming those who go to the Dark Side do so for power . It's pretty much rampant in the EU, but it flies directly against the only dialog we have of it in the show.
"Is the Dark Side stronger?" "No, no, no. Quicker, easier, more seductive."
Nothing about being 'more power', there. Indeed, the only guidance Yoda really gives as to what leads TO it...
"Yoda: Afraid to lose her I think, hmm?
Anakin: What has that got to do with anything?
Yoda: Everything! Fear is the path to the dark side. Fear leads to anger. Anger leads to hate. Hate leads to suffering. I sense much fear in you."
(Or if you insist on the OT version - "But beware. Anger, fear, aggression. The dark side are they. Once you start down the dark path, forever will it dominate your destiny.")
Again, nothing about 'craving power'. The path to the Dark Side, at least as presented on-screen (and as noted, the EU really jumped the shark on this) is all about being afraid . It's the path not of the strong, but of cowards and the weak.