I don’t do cross hatching much, but I know the more crosses/lines you do, the darker that area will look, and the more spaced out they are, the lighter it will look. For painting, I found it was easier to start with the lights and then gradually add the darker shades after. Its hard to make a dark color lighter if you mess up. I don’t necessarily know if there’s much of a fast way to apply shading though, i mean if you want it to look good you should probably spend a good amount of time on it. Unless you want it more abstract maybe, but even those take some time. If you want a more abstract feel I say go with cross hatching, which will probably not take as long as if you used gradation. Just make sure you have a light source so you know where to shade, or at least picture where the light source would be if you don’t have one.