That is exactly how jaconda.im is working now, everybody in the room can send emails into the room.
Cool! Do you use Telegram as a backend for jaconda.im as well? If so, then it's also cool to see somebody giving Slack some competition with a more open backend server.
Jaconda for Telegram works in a different way compared to XMPP Jaconda.im, it is possible to stitch them together but it's a bit too early at the moment.