"What is/are the best scholarship/overviews/studies on Latin literature as a whole?"
I know the majority of questions on this site are about the grammar, but I can't imagine there's not a major overlap between those interested in the Latin language and those interested in Latin literature.
The question might have to be tweakedanswers should recommend and even broken up into two or more depending on how precise we want toevaluate overviews of the development of Latin literature. The division can be anywhere (so Classical Latin, Silver Age Latin, Medieval Latin, etc. all being acceptable).