Hi @good-karma I'm not sure if I would even advocate private messages at all at Steemit (app or main site), let alone storing them for 7 days.
Why? -
I already get enough messages by people paying 0.001 SBD and sometimes even 0.001 Steem itself to send a memo with their message. Often times with offers to sell some service to me.
if Steemians could send private messages for free I'd probably get thousands of them a day.
Or would the private messages not really be "free" for the sender?
If I have no idea what I'm talking about please feel free (anybody) to tell me to be quite.