We have to make a distinction between communications with comics pros and communications with fans.
A pitch is generally a communication with pros. It's what a writer does if he or she has an idea has for a character. Or it may be something an editor puts in writing to explain a vision about characters to new staff.
There are all sorts of efforts to promote a book to fans, but these rarely involve pitches. We may sometimes see pitches as extras, although that's usually preaching to the converted in that it's something shown to fans who are already predisposed to like that thing.
Pitches will often cover stuff that isn't meant for communication with fans, such as where a story's going.
Brevoort did have a five page manifesto for the books leading into Brand New Day that was collected in the Swing Shift Director's Cut. He makes several comments about where they would go with the series, and with Peter being single.