I don't necessarily think the punishment was hard enough to prevent similar future behavior by the Patriots or other teams, but I'm not sure exactly what punishment would ever prevent similar behavior in the future. Taking away the win might have been a good component of a tough enough punishment, but hard to tell for sure.
Some people discussing the event at another site I frequent had suggested that there needed to be a several game suspension for Belichick. That might have helped too, but then again the team might have gone on a winning streak with someone else at the helm so what would have happened except for some time off for Belichick??
If you enforced a forfiet or several forfiets of games on the Patriots then their opponents unfairly benefit and it affects the competitive balance of the entire NFL.
A mess no matter what is done.