Just like the Layers panel, it would beneficial to have a folder structure for materials. It gets unwieldy after the first 30.
The issue with tags is that you got to remember the keywords you used to create them, often months ago (though the drop-down helps), you still have to reach for the search bar instead having a visual hierarchy at a glance, or the ability to rearrange the groupings visually.
Also, once a tag is isolated you can no longer search for a name within that tag list of materials ?
Is it safe to assume that about 95% of all industrial designers and architects use Vray (which has it’s own rendering interface) and that keeps most people from noticing the native Rhino UI rough edges ?
Do you know if Vray materials show up in the native Materials Panel of Rhino ? (so they would blend in the same list with materials from Cycles or other render engines ?)