I totally change up the gauges of wire depending upon the type of wrapping. The tiny strands are always 26g or 28g; the thicker armatures range from 12g to 18g.

There are a number of different styles of wire wrapping; some are more flowy and organic while others are more symmetrical and calculated. I'm not sure where you fall on that spectrum but I browsed the jewelry books on Amazon when I got started in it, and chose a few of the top sellers that appealed most to me.