Indeed... sure he'd be somewhat responsible for a few deaths here and there on the ship, but they was usually to help drive home his point (like those sucked away by the borg when they started hacking up the ship)
A lot of people, both inside the ST universe and outside as viewers, considered Q as a trouble maker who only wanted to torment lesser species simply because he could and it amused him.... but just about every time he was on an episode, he was also proving a point or teaching a lesson...... of course in his own entertaining way.