As a new user of QGIS, one of the tasks I frequently perform is creating a layer where polygons are colored by class, classified by some nominal field in the attribute table. I have developed a habit of switching to the old symbology, because it makes this task easy for an arbitrary number of classes and I can re-randomize the colors until I'm happy with the results. I haven't found any way to do the same thing with the new symbology. The closest I've found is to select "categorized" in the new symbology and select a color ramp, which works well for ordinal data but not so much for nominal categories. I presume that such an important function was not lost in the design of the new symbology, but that I've simply been unable to find it in the manual. I'd prefer to work with the new symbology, simply because that's the direction that QGIS development is going.
Can someone explain or direct me to appropriate documentation of how to accomplish this?