If I may chime in, IMHO a Material Library such as the one you have in 3ds Max would be a great stand-in or placeholder for a full-blown material editor or wizard (which, I imagine would require quite a bit more coding), just as a start.
Something that allows people to select from the base materials you have in the library and then swap out texture maps, for example, in places that necessitate it.
If I remember correctly, the Maxwell folks went through quite a few iterations and versions of their plugin before they ended up with the material wizard, so it's not something that I would have expected right off the bat.
But having a Material library with base sample materials would be a great start to working with and/or creating high-quality Corona materials, so this is definitely a worthwhile idea.
I use the 3ds Max Corona material library all the time now, and just adjust where necessary and I would predict that many ArchiCAD users would end up doing the same with a similar library in ArchiCAD.