This is a small suggestion which I think could be implemented easily, but at the same time solve an annoying problem
Why not to make the "characters left" box in bb-mails more evident, in order to prevent sending/receiving cut mails? Or, maybe, not letting the mail to be sent if the characters are too much, like when the object field is not filled.
It happens to me quite often that I receive a mail and I have to ask to the sender to rewrite it because it was cut. It's pretty tedious for both.