I'm rejecting this, simply on the basis that there's no real reason to distinguish it from a blacklist.
Now, a weekban I could see some value in, if anyone wants to argue for that. But for future reference, any request for new punishment levels should give specific examples of user behavior that would fall into each level.
It's important to note that many rooms in PS! follow punishment systems in their own way - especially in regards to 0-tol (some rooms have that, some don't). This is why I see great potential in the week ban punishment, especially considering the varying/different policy systems each room has. It can be of great help because they could be reserved for users who are not far from being blacklisted, yet a blacklist would not suffice either because the user did not do enough to qualify for one. In my mind, this is how I would picture each of these separate punishments,
including the week ban.
Two-day ban - Reserved for users who have been negative contributors to the chat, and/or have not learned from past warns/mutes.
Week ban - Reserved for users who have returned without any hint of improvement and insist on being negative/toxic/antagonizing/etc.
Blacklist - Consistently bad user who, despite several warns/mutes/bans (including a week ban), shows no sign of improvement, and therefore no longer has the right to stay in the room for a whole year.
I think having this command as an option allows for better flexibility - rooms can use it or leave it, but it can really help in particular situations such as the aforementioned 0-tol users / long time bad contributors. I can imagine this would immediately precede a blacklist. Since I've staffed in a few other rooms in the past, I can safely assume that the policy structures are different for many of them and this command can really be useful when determining the most appropriate punishment for a particular user(s).
If there's any situation I've missed where this command could be of use, feel free to add to it, but I'm overall supporting week ban as a punishment option.