hi,
i also would like to see it implementet this way, this also solves the problem of white on black or black on white highlights because everybody can set its own preferences.
my suggestion would be to implement this as variables in the colors of the highlights. so one can to foregroundColor = "$STRING"; or something like that.
it would be probably also a good idea to be able to set vaiables like this in the beginning (or anywere else) of a highlight file so it would be faster to adjust if something changes.