Agreed with most of your posting G, but some reservations about this:
"All performers have to develop a rapport with their audience and that goes for singers as well as musicians."
I believe that if a singer>musician has a rapport with their song or their piece of music, the listener will develop a rapport with you.
An old singer once told me "if you like your songs enough it's not difficult to get others to feel the same about them"
A win-win situation all round - you enjoy your singing as much as your listeners enjoy hearing you.
Jim Carroll