The English term 'visage' has two meanings: 1: the appearance conveyed by a person's face; 2: the human face (`kisser' and `smiler' and `mug' are informal terms for `face' and `phiz' is British)
The Human face, this is also correct standard English. for example a sketch called Visage de Jeanne D"arc. ( Face of Joan of Arc).
my pretty face
It means "I like your looks".
yes, pretty face I suppose it's meant as a term of endearment, although it is not one that I've heard often