Hey @dave7atgotsky.5512! 
I’ve added your requests for the mailbags and the “Answer Man” replies to our list for the team in charge of these. In the future, we do have a thread dedicated to DCUI suggestions here where we typically collect feedback but here works as well!
Regarding who is responsible for selecting the letters, I will take a look into this and one of us on the moderator team will get back to you once we track down the answer! 