More flexible PM permission options

[boredinsomniac]

Title
More flexible PM permission options

Short, concise description of the idea
If my settings don't allow someone to PM me, and I PM that person, they should be able to reply to me in spite of my settings. I should also be able to exempt specific usernames from my chosen restrictions.

Full description of the idea
Presumeably, if I don't want to talk with someone, I won't message them (well, in a perfect world, anyway). PM-ing someone should signal that regardless of my chosen settings, I am willing to communicate with that person. This person could be allowed to reply for a certain time period after I sent the message, to avoid giving someone carte blanche by messaging them once.

Also, we can already override the settings by banning specific usernames, so it would make sense to be able to override them by allowing specific usernames. I'm thinking that although people won't want everyone they message to be able to message them forever, they would like to grant long-term permission to specific people.

If this is implemented, when you send a message to someone who can't normally PM you, you should get a confirmation screen with a warning and the option of adding them to the allowed list:

"If you send this message, this person will be able to reply to you for one week, in spite of your settings. If you would like this person to always be able to message you, ticky."
An ordered list of benefits

• More intuitive - a lot of people sending messages probably assume that the recipient can respond, when that's not the case.
• Less frustration! No more getting messages you can't reply to.
• The allowed list provides more flexibility in deciding who can message you.
• This would enable people to set PM permissions to "none" but still list specific people who would be allowed to send messages.

An ordered list of problems/issues involved

• Things would become more complicated (both from user and support perspectives) with more possible permission arrangements.
• People who only add allowed users through the confirmation screen might think there's no other way to edit the allowed list, and specifically that they can't remove anyone from it once added.