OK, so I got some themes to give ShapeShifter a try, as I had said, 'Good Grey' looks very nice, and some apps look even better with it, e.g. Mail.app.
I find that Netscape (I think the same goes to Mozilla) under the 'Smoke' theme (note, this is a Netscape / Mozilla theme, not a Mac OS theme) seems fully integrated with 'Good Grey', very very pleasant.
We are here on Earth to do good to others. What the others are here for, I don't know.