Grease pencil feature request - Rain, snow, lightning fog, fire effects presets

It would be nice to have some rain - and raindrop effects, snow, lightning, fire, explosion, fog, magic gizmo, volumetric light, caustics, particle illusion style preset effects in Grease Pencil. Perhaps a good idea for an addon? Fog or volumetric light is hard to do in raytracing, if you could semi transparant layer these effects on top of a 2D-3D render that would be great. Wtih a preview animation in the browser.