Goodell sets precedent
Though his penalties for repeat violators will be severe, he is going to be fair. Look at the cases of Johnson and Chris Henry. Each received eight-game suspensions, but each player had some kind of conviction or two against them.
In the case of Johnson, he served 60 days in jail for violation of his probation. Goodell gave each the ability to come back and restore their status and both appeared to welcome the chance. Henry never threatened to appeal his suspension. Johnson doesn't plan to appeal either, and he sounded appreciative for the way Goodell handled it.