I cannot speak for Kostya, the app developer.
Just in case you haven't noticed, and it would be helpful: in the situation like yours, - there is an arrow and indent for the recipient's name/address.
Also, for the view in Smart Folder, there is a configuration option: Settings -> Smart Folder -> "Show sent messages with you as sender". I am not sure if it works only for the messages stored in the "Sent" in case those are included, or _all_ messages that are from yourself.