It really depends, in flash it depends the zooming and the brush size, for example, you can do storyboards or sketches in any settings, but when youre going to clean the lines or do final touches you have to zoom in and select select a brush size with pressure, like that every drawing is gonna have the same line size, the same composition.
Now, for the smoothness, that depends too, of course it its a drawing you wont use a super high smoothness. In my case i use a low one cause it gives a scratchy look, maybe a 20 - 22 smoothness, or sometimes i use 0 smoothness so the lines look like some photoshop brushes.
As i said man, it really depends. I think gonzo uses a 35- 40 smoothness