Is A Materialist View Less Parsimonious?

Dirt is more plausible. At least it doesn't hide from us or expect us to have faith in it.

We can see how sand is sculpted into dunes by the wind. We can see how stone is sculpted into arches, etc. by the wind. The wind is a known entity.You are proposing an additional entity, an unknown and unevidenced entity - a designer or "god". Hence, your scenario is inerently less parsimonious.

It isn't just the raw number of asumptions that matter. Quality of assumptions is more important than quantity. If I make a thousand small assumptions, all based on real-life observations, that's much better than making one huge assumption based on nothing.(By the way, I don't even like caling God an assumption. In science, assumptions don't float around isolated in space; they're all interconnected. The conclusion from one experiment is the assumption for another. God doesn't qualify.)