No, I mean customizing the generated headline. Instead of just title, to be like:

* Author (year) /Title/. Publisher

Bests

Ypo <ypuntot@gmail.com> writes:

Then, is it not possible to customize the entry generated with 
org-bibtex-create?

You mean fields?
Everything is defined in `org-bibtex-types', but it is not currently a defcustom.

I see no problem adding user types.