Yes, a distant/directional light would be useful, we’ll try to get this into an upcoming version.
I don’t think there’s any issue with the scene scale in the example you provided, the shadows seem correct after adjusting the lights a bit.
Most of the noise is coming from the quad area light, which is creating noisy soft shadows since it is quite close to the scene. I changed it to a point light, and also set it to “No falloff” which is a better approximation to the distant light. I increased the intensity to 200 to compensate for these changes. The phase function parameter of 0.99 was a bit extreme, with this setting almost none of the light will be scattered into the camera, unless the camera is looking directly at the light. It’s not really a problem, but does make things harder to tweak. I changed it to 0.8, in general probably 0.9 or 0.95 should be the maximum.
Here’s the result with the light moved a little higher overhead, so that we get shadows cast from the walls of the canyon:
This was using the ‘Low’ template, with minimum/maximum progressions set to 20/100. I also increased the implicit feature size in the shader to 5.0. Since the volume is uniform this is actually safe, and gives a nice performance improvement.
Also I could reproduce the crash you had with the ImageField node, so we’ll debug and fix it.