I guess there is no point to build a Material UI until you have the right material model to work with. It should be able to represent most of the surfaces we see everyday, They keep inventing new materials, the buggers, so it’s ok not to include the latest nano-tech whatever thingy.
I think there should be one material layer type for all opaque surfaces, and another for transparent volumes.
One more for ‘soft volumes’ like luminous gasses / clouds.
And a thin sheet material layer ofcourse..
If they can combine into one UI like Maxwell did that’s cool but perhaps maxwell combined everything too much, I’m not sure.