For what it is worth, if an aircraft tells me his callsign and idents and it is an aircraft I am expecting, then I am quite happy.
I believe that the main reason for the ident is so that the computer can find the aircraft and update all its bits and pieces.
If we say it it keeps SRG happy.
I think that if an aircraft uses a callsign that I see on the radar using code/callsign, then that is good enough for an ident.
No doubt lots of Controllers are now going to disagree with me.
Pilots, on first call please give your current altitude so that I can verify your mode 'C'