Interesting question Mark. For most of my bowls I use a 3/8" or 1/2" traditional bowl gouge (Ashley Iles) and I've got one groound at a steep angle for deeper bowls. It the shape is heading towards a vase i.e much deeper, I use a Woodcut Proforme, And I will admit to occasionallly using a curved scraper in shear mode for knarly grain. All rather traditional but that's how my father and other turners I admire, have done it, which works for me.