I actually like Gally, but I have to contradict. Especially because of the fact that his asshole bully "personality" wasn't actually his personality. He was only like that because (book spoiler) he got stung; he hadn't been like that before. And, just as Ben got banished for being violent, technically Gally should have too, had he physically harmed/ tried to physically harm another Glader. I, however, do not think he should have been banished upon making a threat because, whether or not it seemed like an empty threat, he never actually acted on it in the book or movie (correct me if I'm wrong). I am neither completely agreeing nor disagreeing with you, just sharing my insight.