I wonder if anyone has written a solution for changing the face by some
kind of style-sheet that is set according to the "type" (or flavor) of the
org-mode file?

My main org-mode file is a journal where 1-star always is used to the
current date. I therefore like to have it small, e.g. 100% non-bold. 2-star
is 140% though.

On the other hand, when writing non-journal files, I would like to have
1-star as e.g. 160% to indicate a title.

Does someone have any idea of how to implement this?

Thanks!
Dov