I
t was indeed easier than I had thought. I tested the modified function on my reading list file and it works as expected under most conditions (It plays well with other variables etc.). The only exception was the previously mentioned issue with nonstandard bibtex types. If I have time this weekend, I will try to look into this problem. (I think it might be time to break down and actually learn lisp.)
Attached is the requested diff. In addition to adding the new variable `org-bibtex-tags-inherit' and editing the function `org-bibtex-headline', I modified a couple of customize doc strings to reflect the change. I also edited one doc string that seemed to refer to an old variable that is no longer in use.