> These expressions are (or at least should be) functions on syntactic forms - syntax transformers.

I don't really agree with this. Backquote is just shorthand for a bunch of consing that makes the end result more clear. Macros are one application where being able to sort of template lists is very useful, but they're not the only one. As well, I think the tendency for people to learn backquote as a companion to defmacro tends to confuse people about how defmacro works.