I suggest that when you send a tell to the DM channel (either using the DM chat mode or the /dm prefix) that you get a feedback echo of your tell/message in the main chat, pretty much like on CoA.
This is useful for seeing what you wrote. Sometimes you write something wrong and it's good to be able to fix it, so that you can make yourself understood. Besides, it just feels odd to send a message and then not see it.
Good idea. I often wonder if I wrote my sentence right on the channel, or if something was unclear, a bit too nebulous.
I think double-checking before you type a request would resolve the matter, rather than rigging a feedback setting up.
Deception.......... You double check. The rest of us would like to see what we sent.