ganneff asked developers to use BTS to request override changes, see hit post. Yeah, of course I'll do so.
The format for such bug reports against the ftp.debian.org pseudopackage: Subject: override: PACKAGE1:section/priority, [...], PACKAGEX:section/priority Include the justification for the change in the body of the bug please.
But... why "extra" is default priority value of template? Most of the packages would be "optional" , so it is suitable for default, I think.