Continuing to play more with MASH in Autodesk Maya, I came up with this experiment: I used a ramp node with a wave to mask where the hexagons are placed, then randomized their scale. Applied a dark stain on the uncut top, and a natural stain on all the hexagons. Material is a reclaimed redwood beam.
About half an hour of modeling in Maya, and 1h45min on the X-Carve CNC with a 1/8″ 1-flute upcut endmill. Probably another half hour of sanding.