I just have to absolutely disagree with the characterization of Benedict Arnold as egotistical and treacherous.
A man is judged by his deeds. Treason > military service. His service in Quebec was a disaster, and whatever field exploits he enjoyed at Saratoga, such were the advantages enjoyed there by the Rebels that Gates was assured of victory anyway.
His treason not only was preparing to help sever the Rebels LOC between New York and New England, but would have given Arnold the opportunity to hand Washington, Alexander Hamilton, and Lafayette over to the British.
Agreed, the amount of crap he had to put up from his 'superiors' and the work he did for the revolutionary cause should be more well known. It's no surprise he switched sides considering the mount of backstabbing and treachery against him alone. There's only so much you can take and take and take before you just see the writing on the wall.
SMICE, the acronym of Treason:
Sex: His newlywed Loyalist wife, who was in on his treason up to her pretty little eyebrows
Money: Oh yes
Ideology: No
Compromise: The moment he heard of Andre's capture
Ego: I think you made a pretty good argument for that yourself. Thank you.
That's four out of five. I'd say that's a good definition of a very UNrighteous traitor.
Remember that even the British were disgusted with him.
And as a life long native of Connecticut, I am well aware of how my fellow Nutmegger spent most of his British military career burning our own state to the ground.

When he wasn't doing the same to Virginia. Being a British regimental colonel or brigadier of some garrison somewhere, or serving in a line command in New York is one thing. Turning fire, rapine, and pillaging upon your own once neighbors is another.
I think a defection on that high of a level would cause much more problems than it could possibly be worth for intelligence. OTL, the defection of Benedict Arnold caused outraged and galvanized the population more than anything, but if it came at the same time as a perception of losing or of the tide turning, the defection of someone so high up would be heavily demoralizing.
Hear-hear!