"punishment" for the sake of accountability doesn't gain the sinner anything.
Look at the case of the Prodigal Son. The father could have easily been justified for heaping additional punishment on his boy for his poor choices. Instead, he told the older son who wanted JUSTICE that his son had already suffered enough, it was time to repent. The Son who made the correct choice will always be ahead. The one who sinned knew what he did and payed for it. There was no need for additional punishment for the sake of punishment.
So sure, I DO believe that suffering something awful as a result of poor choices is punishment enough. It's not complete repentance, but it's the first step.