With my jewelry, I mix high and low the way I do my clothes. I wear a diamond wedding band regularly but will match it with everything from Marc Jacobs pendant watches to Kenneth Jay Lane bracelets, JCrew rings to Ippolita necklaces. It's vibrant and fun, as long as the pieces don't clash or I don't pile too much on (which is never really an issue).
And as I carry mainly GH Balenciaga bags, I don't worry too much about matching the jewelry to the hardware - again, it's fun if there's a mix.