The reason there were no Maquis flashbacks is because they're the most boring terrorists ever. They're like those guys who petition for a rally to march through the streets and protest something-or-other, but when the day comes for the march they just go "ey, who can be bothered already?". Hence Chakotay. He's no terrorist: he's the kind of guy who'd rather be sitting in Starbucks sipping a Frappuccino.
Eddington is literally the only guy among the whole lot of them who actually had the balls to go the extra mile, and even then it's only because he's a fucking nut-job psycho. He'd have to have been the kind of man who picked the wings off flies as a kid.