Elaborating on certain aspects:
I would imagine that, in normal use, this device would be the first in a project. It would likely apply a default terrain (Maybe an option to decide what flavor of noise to use for the base terrain, or an input where a generator device could be plugged in?). The device would then define plate boundaries (Another possible area for improvement would be separating major plates and minor plates. For example, Earth has, if I recall correctly, 7 major plates and 8 minor plates, resulting in my 15 plate default) and densities based on user selection/input. The movement speed and simulation length could then be tweaked until a desirable world has started. This device could then be followed up with a normal World Machine workflow adding erosion, terracing, snow, etc.
Plate density would affect the likelihood of a plate to sublimate. For example, when a low density plate meets a high density plate, the higher density plate sinks below, causing a subduction zone near the coast, and the possibility for some lower inland mountains/hills.
Plate direction would be determined “behind-the-scenes” in the device, and would determine where and when plates converge and diverge. This would also inform plate rotation and movement, as a plate converging on the lower half of another plate would cause it to start rotating in that direction, increasing the complexity of the boundary zones.
I think the absolute biggest issue with this proposed device is the amount of cross and back referencing required. Each step would need to go back and refer to every other step, as well as every factor involved in the current step, which I could see very easily locking up even a high end processor for high resolution builds. Even with a simple two plate setup, it would have to constantly reference the convergent boundary to determine how high the mountains rise, and the divergent boundary to determine the width and depth of the trench/rift.
Beyond that, a weakness I only just now realized is that for a truly realistic terrain, erosion and tectonic shift would have to be happening simultaneously, as tectonic shift is generally measured in millions of years. To be calculating the tectonic shift as well as the erosion happening, especially with tectonic shift affecting erosion, might be outside the realm of what we’re technologically capable of right now at a consumer level.