Request Traffic - ATC do NOT always give me traffic when I would like it. They can't read my mind. If I know from prior experience and local knowledge that there are likely to be several aircraft given to me as traffic I want to find out about them in plenty of time BEFORE I make the initial CTAF call and before descent. As I'm often chugging around at 2-4000 feet TOD is after the inbound CTAF call so when ATC forgets about me in the non-airline piston twin I need to request traffic so I can start to sort out a plan of attack for separation and know which aircraft I should expect a response from. HOWEVER the pilots which say "Center, ABC, IFR Chieftain 1 POB taxing BLA for BLA runway 23 REQUEST TRAFFIC" really give me the sh*ts. He's going to give you traffic mate, that's what the taxi call is for.
"Standby for departure" I know this is an unnecessary call but it seems every time I make an airborne call with POB soon after take off to initiate SARWATCH and I haven't had a chance to calculate an accurate ETA for my next point I get an ATC response of "go ahead with departure" and I end up having to tell them "Standby" anyway.