well... Preview for PMs before sending them due to same Matter like for editing Posts and an Archive could help to organize received PMs resp to sort out PMs which shall not get deleted anytime ... so my PMBox grows and grows..
edit Im not sure if Term Request in Thread-Title is the that I did want to take - but it seems like I can't change it anymore. Editing (Sub)Titles could be usefull ... so another ... Recommendation